ceph: Use pseudo-random numbers to choose mds #1

6uv1s · 2013-04-12T18:05:09Z

We don't need to use up entropy to choose an mds,
so use prandom_u32() to get a pseudo-random number.

Also, we don't need to choose a random mds if only
one mds is available, so add special casing for the
common case.

Fixes http://tracker.ceph.com/issues/3579

Signed-off-by: Sam Lang sam.lang@inktank.com

We don't need to use up entropy to choose an mds, so use prandom_u32() to get a pseudo-random number. Also, we don't need to choose a random mds if only one mds is available, so add special casing for the common case. Fixes http://tracker.ceph.com/issues/3579 Signed-off-by: Sam Lang <sam.lang@inktank.com>

Commit 84c1754 (ext4: move work from io_end to inode) triggered a regression when running xfstest #270 when the file system is mounted with dioread_nolock. The problem is that after ext4_evict_inode() calls ext4_ioend_wait(), this guarantees that last io_end structure has been freed, but it does not guarantee that the workqueue structure, which was moved into the inode by commit 84c1754, is actually finished. Once ext4_flush_completed_IO() calls ext4_free_io_end() on CPU #1, this will allow ext4_ioend_wait() to return on CPU #2, at which point the evict_inode() codepath can race against the workqueue code on CPU #1 accessing EXT4_I(inode)->i_unwritten_work to find the next item of work to do. Fix this by calling cancel_work_sync() in ext4_ioend_wait(), which will be renamed ext4_ioend_shutdown(), since it is only used by ext4_evict_inode(). Also, move the call to ext4_ioend_shutdown() until after truncate_inode_pages() and filemap_write_and_wait() are called, to make sure all dirty pages have been written back and flushed from the page cache first. BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<c01dda6a>] cwq_activate_delayed_work+0x3b/0x7e *pdpt = 0000000030bc3001 *pde = 0000000000000000 Oops: 0000 [#1] SMP DEBUG_PAGEALLOC Modules linked in: Pid: 6, comm: kworker/u:0 Not tainted 3.8.0-rc3-00013-g84c1754-dirty #91 Bochs Bochs EIP: 0060:[<c01dda6a>] EFLAGS: 00010046 CPU: 0 EIP is at cwq_activate_delayed_work+0x3b/0x7e EAX: 00000000 EBX: 00000000 ECX: f505fe54 EDX: 00000000 ESI: ed5b697c EDI: 00000006 EBP: f64b7e8c ESP: f64b7e84 DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068 CR0: 8005003b CR2: 00000000 CR3: 30bc2000 CR4: 000006f0 DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 DR6: ffff0ff0 DR7: 00000400 Process kworker/u:0 (pid: 6, ti=f64b6000 task=f64b4160 task.ti=f64b6000) Stack: f505fe00 00000006 f64b7e9c c01de3d7 f6435540 00000003 f64b7efc c01def1d f6435540 00000002 00000000 0000008a c16d0808 c040a10b c16d07d8 c16d08b0 f505fe00 c16d0780 00000000 00000000 ee153df4 c1ce4a30 c17d0e30 00000000 Call Trace: [<c01de3d7>] cwq_dec_nr_in_flight+0x71/0xfb [<c01def1d>] process_one_work+0x5d8/0x637 [<c040a10b>] ? ext4_end_bio+0x300/0x300 [<c01e3105>] worker_thread+0x249/0x3ef [<c01ea317>] kthread+0xd8/0xeb [<c01e2ebc>] ? manage_workers+0x4bb/0x4bb [<c023a370>] ? trace_hardirqs_on+0x27/0x37 [<c0f1b4b7>] ret_from_kernel_thread+0x1b/0x28 [<c01ea23f>] ? __init_kthread_worker+0x71/0x71 Code: 01 83 15 ac ff 6c c1 00 31 db 89 c6 8b 00 a8 04 74 12 89 c3 30 db 83 05 b0 ff 6c c1 01 83 15 b4 ff 6c c1 00 89 f0 e8 42 ff ff ff <8b> 13 89 f0 83 05 b8 ff 6c c1 6c c1 00 31 c9 83 EIP: [<c01dda6a>] cwq_activate_delayed_work+0x3b/0x7e SS:ESP 0068:f64b7e84 CR2: 0000000000000000 ---[ end trace a1923229da53d8a4 ]--- Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Jan Kara <jack@suse.cz>

With git commit c705c78 "acpi: Export the acpi_processor_get_performance_info" we are now using a different mechanism to access the P-states. The acpi_processor per-cpu structure is set and filtered by the core ACPI code which shrinks the per_cpu contents to only online CPUs. In the past we would call acpi_processor_register_performance() which would have not tried to dereference offline cpus. With the new patch and the fact that the loop we take is for for_all_possible_cpus we end up crashing on some machines. We could modify the loop to be for online_cpus - but all the other loops in the code use possible_cpus (for a good reason) - so lets leave it as so and just check if per_cpu(processor) is NULL. With this patch we will bypass the !online but possible CPUs. This fixes: IP: [<ffffffffa00d13b5>] xen_acpi_processor_init+0x1b6/0xe01 [xen_acpi_processor] PGD 4126e6067 PUD 4126e3067 PMD 0 Oops: 0002 [#1] SMP Pid: 432, comm: modprobe Not tainted 3.9.0-rc3+ #28 To be filled by O.E.M. To be filled by O.E.M./M5A97 RIP: e030:[<ffffffffa00d13b5>] [<ffffffffa00d13b5>] xen_acpi_processor_init+0x1b6/0xe01 [xen_acpi_processor] RSP: e02b:ffff88040c8a3ce8 EFLAGS: 00010282 .. snip.. Call Trace: [<ffffffffa00d11ff>] ? read_acpi_id+0x12b/0x12b [xen_acpi_processor] [<ffffffff8100215a>] do_one_initcall+0x12a/0x180 [<ffffffff810c42c3>] load_module+0x1cd3/0x2870 [<ffffffff81319b70>] ? ddebug_proc_open+0xc0/0xc0 [<ffffffff810c4f37>] sys_init_module+0xd7/0x120 [<ffffffff8166ce19>] system_call_fastpath+0x16/0x1b on some machines. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Booting with 32 TBytes memory hits BUG at mm/page_alloc.c:552! (output below). The key hint is "page 4294967296 outside zone". 4294967296 = 0x100000000 (bit 32 is set). The problem is in include/linux/mmzone.h: 530 static inline unsigned zone_end_pfn(const struct zone *zone) 531 { 532 return zone->zone_start_pfn + zone->spanned_pages; 533 } zone_end_pfn is "unsigned" (32 bits). Changing it to "unsigned long" (64 bits) fixes the problem. zone_end_pfn() was added recently in commit 108bcc9 ("mm: add & use zone_end_pfn() and zone_spans_pfn()") Output from the failure. No AGP bridge found page 4294967296 outside zone [ 4294967296 - 4327469056 ] ------------[ cut here ]------------ kernel BUG at mm/page_alloc.c:552! invalid opcode: 0000 [#1] SMP Modules linked in: CPU 0 Pid: 0, comm: swapper Not tainted 3.9.0-rc2.dtp+ #10 RIP: free_one_page+0x382/0x430 Process swapper (pid: 0, threadinfo ffffffff81942000, task ffffffff81955420) Call Trace: __free_pages_ok+0x96/0xb0 __free_pages+0x25/0x50 __free_pages_bootmem+0x8a/0x8c __free_memory_core+0xea/0x131 free_low_memory_core_early+0x4a/0x98 free_all_bootmem+0x45/0x47 mem_init+0x7b/0x14c start_kernel+0x216/0x433 x86_64_start_reservations+0x2a/0x2c x86_64_start_kernel+0x144/0x153 Code: 89 f1 ba 01 00 00 00 31 f6 d3 e2 4c 89 ef e8 66 a4 01 00 e9 2c fe ff ff 0f 0b eb fe 0f 0b 66 66 2e 0f 1f 84 00 00 00 00 00 eb f3 <0f> 0b eb fe 0f 0b 0f 1f 84 00 00 00 00 00 eb f6 0f 0b eb fe 49 Signed-off-by: Russ Anderson <rja@sgi.com> Reported-by: George Beshers <gbeshers@sgi.com> Acked-by: Hedi Berriche <hedi@sgi.com> Cc: Cody P Schafer <cody@linux.vnet.ibm.com> Cc: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We can deadlock (s_active and fcoe_config_mutex) if a port is being destroyed at the same time one is being created. [ 4200.503113] ====================================================== [ 4200.503114] [ INFO: possible circular locking dependency detected ] [ 4200.503116] 3.8.0-rc5+ #8 Not tainted [ 4200.503117] ------------------------------------------------------- [ 4200.503118] kworker/3:2/2492 is trying to acquire lock: [ 4200.503119] (s_active#292){++++.+}, at: [<ffffffff8122d20b>] sysfs_addrm_finish+0x3b/0x70 [ 4200.503127] but task is already holding lock: [ 4200.503128] (fcoe_config_mutex){+.+.+.}, at: [<ffffffffa02f3338>] fcoe_destroy_work+0xe8/0x120 [fcoe] [ 4200.503133] which lock already depends on the new lock. [ 4200.503135] the existing dependency chain (in reverse order) is: [ 4200.503136] -> #1 (fcoe_config_mutex){+.+.+.}: [ 4200.503139] [<ffffffff810c7711>] lock_acquire+0xa1/0x140 [ 4200.503143] [<ffffffff816ca7be>] mutex_lock_nested+0x6e/0x360 [ 4200.503146] [<ffffffffa02f11bd>] fcoe_enable+0x1d/0xb0 [fcoe] [ 4200.503148] [<ffffffffa02f127d>] fcoe_ctlr_enabled+0x2d/0x50 [fcoe] [ 4200.503151] [<ffffffffa02ffbe8>] store_ctlr_enabled+0x38/0x90 [libfcoe] [ 4200.503154] [<ffffffff81424878>] dev_attr_store+0x18/0x30 [ 4200.503157] [<ffffffff8122b750>] sysfs_write_file+0xe0/0x150 [ 4200.503160] [<ffffffff811b334c>] vfs_write+0xac/0x180 [ 4200.503162] [<ffffffff811b3692>] sys_write+0x52/0xa0 [ 4200.503164] [<ffffffff816d7159>] system_call_fastpath+0x16/0x1b [ 4200.503167] -> #0 (s_active#292){++++.+}: [ 4200.503170] [<ffffffff810c680f>] __lock_acquire+0x135f/0x1c90 [ 4200.503172] [<ffffffff810c7711>] lock_acquire+0xa1/0x140 [ 4200.503174] [<ffffffff8122c626>] sysfs_deactivate+0x116/0x160 [ 4200.503176] [<ffffffff8122d20b>] sysfs_addrm_finish+0x3b/0x70 [ 4200.503178] [<ffffffff8122b2eb>] sysfs_hash_and_remove+0x5b/0xb0 [ 4200.503180] [<ffffffff8122f3d1>] sysfs_remove_group+0x61/0x100 [ 4200.503183] [<ffffffff814251eb>] device_remove_groups+0x3b/0x60 [ 4200.503185] [<ffffffff81425534>] device_remove_attrs+0x44/0x80 [ 4200.503187] [<ffffffff81425e97>] device_del+0x127/0x1c0 [ 4200.503189] [<ffffffff81425f52>] device_unregister+0x22/0x60 [ 4200.503191] [<ffffffffa0300970>] fcoe_ctlr_device_delete+0xe0/0xf0 [libfcoe] [ 4200.503194] [<ffffffffa02f1b5c>] fcoe_interface_cleanup+0x6c/0xa0 [fcoe] [ 4200.503196] [<ffffffffa02f3355>] fcoe_destroy_work+0x105/0x120 [fcoe] [ 4200.503198] [<ffffffff8107ee91>] process_one_work+0x1a1/0x580 [ 4200.503203] [<ffffffff81080c6e>] worker_thread+0x15e/0x440 [ 4200.503205] [<ffffffff8108715a>] kthread+0xea/0xf0 [ 4200.503207] [<ffffffff816d70ac>] ret_from_fork+0x7c/0xb0 [ 4200.503209] other info that might help us debug this: [ 4200.503211] Possible unsafe locking scenario: [ 4200.503212] CPU0 CPU1 [ 4200.503213] ---- ---- [ 4200.503214] lock(fcoe_config_mutex); [ 4200.503215] lock(s_active#292); [ 4200.503218] lock(fcoe_config_mutex); [ 4200.503219] lock(s_active#292); [ 4200.503221] *** DEADLOCK *** [ 4200.503223] 3 locks held by kworker/3:2/2492: [ 4200.503224] #0: (fcoe){.+.+.+}, at: [<ffffffff8107ee2b>] process_one_work+0x13b/0x580 [ 4200.503228] #1: ((&port->destroy_work)){+.+.+.}, at: [<ffffffff8107ee2b>] process_one_work+0x13b/0x580 [ 4200.503232] #2: (fcoe_config_mutex){+.+.+.}, at: [<ffffffffa02f3338>] fcoe_destroy_work+0xe8/0x120 [fcoe] [ 4200.503236] stack backtrace: [ 4200.503238] Pid: 2492, comm: kworker/3:2 Not tainted 3.8.0-rc5+ #8 [ 4200.503240] Call Trace: [ 4200.503243] [<ffffffff816c2f09>] print_circular_bug+0x1fb/0x20c [ 4200.503246] [<ffffffff810c680f>] __lock_acquire+0x135f/0x1c90 [ 4200.503248] [<ffffffff810c463a>] ? debug_check_no_locks_freed+0x9a/0x180 [ 4200.503250] [<ffffffff810c7711>] lock_acquire+0xa1/0x140 [ 4200.503253] [<ffffffff8122d20b>] ? sysfs_addrm_finish+0x3b/0x70 [ 4200.503255] [<ffffffff8122c626>] sysfs_deactivate+0x116/0x160 [ 4200.503258] [<ffffffff8122d20b>] ? sysfs_addrm_finish+0x3b/0x70 [ 4200.503260] [<ffffffff8122d20b>] sysfs_addrm_finish+0x3b/0x70 [ 4200.503262] [<ffffffff8122b2eb>] sysfs_hash_and_remove+0x5b/0xb0 [ 4200.503265] [<ffffffff8122f3d1>] sysfs_remove_group+0x61/0x100 [ 4200.503273] [<ffffffff814251eb>] device_remove_groups+0x3b/0x60 [ 4200.503275] [<ffffffff81425534>] device_remove_attrs+0x44/0x80 [ 4200.503277] [<ffffffff81425e97>] device_del+0x127/0x1c0 [ 4200.503279] [<ffffffff81425f52>] device_unregister+0x22/0x60 [ 4200.503282] [<ffffffffa0300970>] fcoe_ctlr_device_delete+0xe0/0xf0 [libfcoe] [ 4200.503285] [<ffffffffa02f1b5c>] fcoe_interface_cleanup+0x6c/0xa0 [fcoe] [ 4200.503287] [<ffffffffa02f3355>] fcoe_destroy_work+0x105/0x120 [fcoe] [ 4200.503290] [<ffffffff8107ee91>] process_one_work+0x1a1/0x580 [ 4200.503292] [<ffffffff8107ee2b>] ? process_one_work+0x13b/0x580 [ 4200.503295] [<ffffffffa02f3250>] ? fcoe_if_destroy+0x230/0x230 [fcoe] [ 4200.503297] [<ffffffff81080c6e>] worker_thread+0x15e/0x440 [ 4200.503299] [<ffffffff81080b10>] ? busy_worker_rebind_fn+0x100/0x100 [ 4200.503301] [<ffffffff8108715a>] kthread+0xea/0xf0 [ 4200.503304] [<ffffffff81087070>] ? kthread_create_on_node+0x160/0x160 [ 4200.503306] [<ffffffff816d70ac>] ret_from_fork+0x7c/0xb0 [ 4200.503308] [<ffffffff81087070>] ? kthread_create_on_node+0x160/0x160 Signed-off-by: Robert Love <robert.w.love@intel.com> Tested-by: Jack Morgan <jack.morgan@intel.com>

The current code makes the assumption that a cpu_base lock won't be held if the CPU corresponding to that cpu_base is offline, which isn't always true. If a hrtimer is not queued, then it will not be migrated by migrate_hrtimers() when a CPU is offlined. Therefore, the hrtimer's cpu_base may still point to a CPU which has subsequently gone offline if the timer wasn't enqueued at the time the CPU went down. Normally this wouldn't be a problem, but a cpu_base's lock is blindly reinitialized each time a CPU is brought up. If a CPU is brought online during the period that another thread is performing a hrtimer operation on a stale hrtimer, then the lock will be reinitialized under its feet, and a SPIN_BUG() like the following will be observed: <0>[ 28.082085] BUG: spinlock already unlocked on CPU#0, swapper/0/0 <0>[ 28.087078] lock: 0xc4780b40, value 0x0 .magic: dead4ead, .owner: <none>/-1, .owner_cpu: -1 <4>[ 42.451150] [<c0014398>] (unwind_backtrace+0x0/0x120) from [<c0269220>] (do_raw_spin_unlock+0x44/0xdc) <4>[ 42.460430] [<c0269220>] (do_raw_spin_unlock+0x44/0xdc) from [<c071b5bc>] (_raw_spin_unlock+0x8/0x30) <4>[ 42.469632] [<c071b5bc>] (_raw_spin_unlock+0x8/0x30) from [<c00a9ce0>] (__hrtimer_start_range_ns+0x1e4/0x4f8) <4>[ 42.479521] [<c00a9ce0>] (__hrtimer_start_range_ns+0x1e4/0x4f8) from [<c00aa014>] (hrtimer_start+0x20/0x28) <4>[ 42.489247] [<c00aa014>] (hrtimer_start+0x20/0x28) from [<c00e6190>] (rcu_idle_enter_common+0x1ac/0x320) <4>[ 42.498709] [<c00e6190>] (rcu_idle_enter_common+0x1ac/0x320) from [<c00e6440>] (rcu_idle_enter+0xa0/0xb8) <4>[ 42.508259] [<c00e6440>] (rcu_idle_enter+0xa0/0xb8) from [<c000f268>] (cpu_idle+0x24/0xf0) <4>[ 42.516503] [<c000f268>] (cpu_idle+0x24/0xf0) from [<c06ed3c0>] (rest_init+0x88/0xa0) <4>[ 42.524319] [<c06ed3c0>] (rest_init+0x88/0xa0) from [<c0c00978>] (start_kernel+0x3d0/0x434) As an example, this particular crash occurred when hrtimer_start() was executed on CPU #0. The code locked the hrtimer's current cpu_base corresponding to CPU #1. CPU #0 then tried to switch the hrtimer's cpu_base to an optimal CPU which was online. In this case, it selected the cpu_base corresponding to CPU #3. Before it could proceed, CPU #1 came online and reinitialized the spinlock corresponding to its cpu_base. Thus now CPU #0 held a lock which was reinitialized. When CPU #0 finally ended up unlocking the old cpu_base corresponding to CPU #1 so that it could switch to CPU #3, we hit this SPIN_BUG() above while in switch_hrtimer_base(). CPU #0 CPU #1 ---- ---- ... <offline> hrtimer_start() lock_hrtimer_base(base #1) ... init_hrtimers_cpu() switch_hrtimer_base() ... ... raw_spin_lock_init(&cpu_base->lock) raw_spin_unlock(&cpu_base->lock) ... <spin_bug> Solve this by statically initializing the lock. Signed-off-by: Michael Bohan <mbohan@codeaurora.org> Link: http://lkml.kernel.org/r/1363745965-23475-1-git-send-email-mbohan@codeaurora.org Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

clk inits on OMAP happen quite early, even before slab is available. The dependency comes from the fact that the timer init code starts to use clocks and hwmod and we need clocks to be initialized by then. There are various problems doing clk inits this early, one is, not being able to do dynamic clk registrations and hence the dependency on clk-private.h. The other is, inability to debug early kernel crashes without enabling DEBUG_LL and earlyprintk. Doing early clk init also exposed another instance of a kernel panic due to a BUG() when CONFIG_DEBUG_SLAB is enabled. [ 0.000000] Kernel BUG at c01174f8 [verbose debug info unavailable] [ 0.000000] Internal error: Oops - BUG: 0 [#1] SMP ARM [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 Not tainted (3.9.0-rc1-12179-g72d48f9 #6) [ 0.000000] PC is at __kmalloc+0x1d4/0x248 [ 0.000000] LR is at __clk_init+0x2e0/0x364 [ 0.000000] pc : [<c01174f8>] lr : [<c0441f54>] psr: 600001d3 [ 0.000000] sp : c076ff28 ip : c065cefc fp : c0441f54 [ 0.000000] r10: 0000001c r9 : 000080d0 r8 : c076ffd4 [ 0.000000] r7 : c074b578 r6 : c0794d88 r5 : 00000040 r4 : 00000000 [ 0.000000] r3 : 00000000 r2 : c07cac70 r1 : 000080d0 r0 : 0000001c [ 0.000000] Flags: nZCv IRQs off FIQs off Mode SVC_32 ISA ARM Segment kernel [ 0.000000] Control: 10c53c7d Table: 8000404a DAC: 00000017 [ 0.000000] Process swapper (pid: 0, stack limit = 0xc076e240) [ 0.000000] Stack: (0xc076ff28 to 0xc0770000) [ 0.000000] ff20: 22222222 c0794ec8 c06546e8 00000000 00000040 c0794d88 [ 0.000000] ff40: c074b578 c076ffd4 c07951c8 c076e000 00000000 c0441f54 c074b578 c076ffd4 [ 0.000000] ff60: c0793828 00000040 c0794d88 c074b578 c076ffd4 c0776900 c076e000 c07272ac [ 0.000000] ff80: 2f800000 c074c968 c07f93d0 c0719780 c076ffa0 c076ff98 00000000 00000000 [ 0.000000] ffa0: 00000000 00000000 00000000 00000001 c074cd6c c077b1ec 8000406a c0715724 [ 0.000000] ffc0: 00000000 00000000 00000000 00000000 00000000 c074c968 10c53c7d c0776974 [ 0.000000] ffe0: c074cd6c c077b1ec 8000406a 411fc092 00000000 80008074 00000000 00000000 [ 0.000000] [<c01174f8>] (__kmalloc+0x1d4/0x248) from [<c0441f54>] (__clk_init+0x2e0/0x364) [ 0.000000] [<c0441f54>] (__clk_init+0x2e0/0x364) from [<c07272ac>] (omap4xxx_clk_init+0xbc/0x140) [ 0.000000] [<c07272ac>] (omap4xxx_clk_init+0xbc/0x140) from [<c0719780>] (setup_arch+0x15c/0x284) [ 0.000000] [<c0719780>] (setup_arch+0x15c/0x284) from [<c0715724>] (start_kernel+0x7c/0x334) [ 0.000000] [<c0715724>] (start_kernel+0x7c/0x334) from [<80008074>] (0x80008074) [ 0.000000] Code: e5883004 e1a00006 e28dd00c e8bd8ff0 (e7f001f2) [ 0.000000] ---[ end trace 1b75b31a2719ed1c ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! It was a know issue, that slab allocations would fail when common clock core tries to cache parent pointers for mux clocks on OMAP, and hence a patch 'clk: Allow late cache allocation for clk->parents, commit 7975059' was added to work this problem around. A BUG() within kmalloc() with CONFIG_DEBUG_SLAB enabled was completely overlooked causing this regression. More details on the issue reported can be found here, http://www.mail-archive.com/linux-omap@vger.kernel.org/msg85932.html With all these issues around clk inits happening way too early, it makes sense to at least move them to a point where dynamic memory allocations are possible. So move them to a point just before the timer code starts using clocks and hwmod. This should at least pave way for clk inits on OMAP moving to dynamic clock registrations instead of using the static macros defined in clk-private.h. The issue with kernel panic while CONFIG_DEBUG_SLAB is enabled was reported by Piotr Haber and Tony Lindgren and this patch fixes the reported issue as well. Reported-by: Piotr Haber <phaber@broadcom.com> Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Rajendra Nayak <rnayak@ti.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Reviewed-by: Mike Turquette <mturquette@linaro.org> Acked-by: Paul Walmsley <paul@pwsan.com> Cc: stable@vger.kernel.org # v3.8 Signed-off-by: Tony Lindgren <tony@atomide.com>

The following issue was reported. WARNING: at net/mac80211/util.c:599 ieee80211_can_queue_work.isra.7+0x32/0x40 [mac80211]() Hardware name: iMac12,1 queueing ieee80211 work while going to suspend Pid: 0, comm: swapper/0 Tainted: PF O 3.8.2-206.fc18.x86_64 #1 Call Trace: Mar 16 09:39:17 Parags-iMac kernel: [ 3993.642992] <IRQ> [<ffffffff8105e61f>] warn_slowpath_common+0x7f/0xc0 [<ffffffffa0581420>] ? ath_start_rx_poll+0x70/0x70 [ath9k] <ffffffff8105e716>] warn_slowpath_fmt+0x46/0x50 [<ffffffffa045b542>] ieee80211_can_queue_work.isra.7+0x32/0x40 Fix this by avoiding to queue the work if our device has already been marked as suspended or stopped. Reported-by: Parag Warudkar <parag.lkml@gmail.com> Tested-by: Parag Warudkar <parag.lkml@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>

Op 23-03-13 12:47, Peter Hurley schreef: > On Tue, 2013-03-19 at 11:13 -0400, Peter Hurley wrote: >> On vanilla 3.9.0-rc3, I get this 100% repeatable oops after login when >> the user X session is coming up: > Perhaps I wasn't clear that this happens on every boot and is a > regression from 3.8 > > I'd be happy to help resolve this but time is of the essence; it would > be a shame to have to revert all of this for 3.9 Well it broke on my system too, so it was easy to fix. I didn't even need gdm to trigger it! >8---- This fixes regression caused by 1d7c71a (drm/nouveau/disp: port vblank handling to event interface), which causes a oops in the following way: BUG: unable to handle kernel NULL pointer dereference at 0000000000000001 IP: [<0000000000000001>] 0x0 PGD 0 Oops: 0010 [#1] PREEMPT SMP Modules linked in: ip6table_filter ip6_tables ebtable_nat ebtables ...<snip>... CPU 3 Pid: 0, comm: swapper/3 Not tainted 3.9.0-rc3-xeon #rc3 Dell Inc. Precision WorkStation T5400 /0RW203 RIP: 0010:[<0000000000000001>] [<0000000000000001>] 0x0 RSP: 0018:ffff8802afcc3d80 EFLAGS: 00010087 RAX: ffff88029f6e5808 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 0000000000000096 RSI: 0000000000000001 RDI: ffff88029f6e5808 RBP: ffff8802afcc3dc8 R08: 0000000000000000 R09: 0000000000000004 R10: 000000000000002c R11: ffff88029e559a98 R12: ffff8802a376cb78 R13: ffff88029f6e57e0 R14: ffff88029f6e57f8 R15: ffff88029f6e5808 FS: 0000000000000000(0000) GS:ffff8802afcc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 0000000000000001 CR3: 000000029fa67000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process swapper/3 (pid: 0, threadinfo ffff8802a355e000, task ffff8802a3535c40) Stack: ffffffffa0159d8a 0000000000000082 ffff88029f6e5820 0000000000000001 ffff88029f71aa00 0000000000000000 0000000000000000 0000000004000000 0000000004000000 ffff8802afcc3e38 ffffffffa01843b5 ffff8802afcc3df8 Call Trace: <IRQ> [<ffffffffa0159d8a>] ? nouveau_event_trigger+0xaa/0xe0 [nouveau] [<ffffffffa01843b5>] nv50_disp_intr+0xc5/0x200 [nouveau] [<ffffffff816fbacc>] ? _raw_spin_unlock_irqrestore+0x2c/0x50 [<ffffffff816ff98d>] ? notifier_call_chain+0x4d/0x70 [<ffffffffa017a105>] nouveau_mc_intr+0xb5/0x110 [nouveau] [<ffffffffa01d45ff>] nouveau_irq_handler+0x6f/0x80 [nouveau] [<ffffffff810eec95>] handle_irq_event_percpu+0x75/0x260 [<ffffffff810eeec8>] handle_irq_event+0x48/0x70 [<ffffffff810f205a>] handle_fasteoi_irq+0x5a/0x100 [<ffffffff810182f2>] handle_irq+0x22/0x40 [<ffffffff8170561a>] do_IRQ+0x5a/0xd0 [<ffffffff816fc2ad>] common_interrupt+0x6d/0x6d <EOI> [<ffffffff810449b6>] ? native_safe_halt+0x6/0x10 [<ffffffff8101ea1d>] default_idle+0x3d/0x170 [<ffffffff8101f736>] cpu_idle+0x116/0x130 [<ffffffff816e2a06>] start_secondary+0x251/0x258 Code: Bad RIP value. RIP [<0000000000000001>] 0x0 RSP <ffff8802afcc3d80> CR2: 0000000000000001 ---[ end trace 907323cb8ce6f301 ]--- Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

This reverts commit 6aa9707. Commit 6aa9707 ("lockdep: check that no locks held at freeze time") causes problems with NFS root filesystems. The failures were noticed on OMAP2 and 3 boards during kernel init: [ BUG: swapper/0/1 still has locks held! ] 3.9.0-rc3-00344-ga937536 #1 Not tainted ------------------------------------- 1 lock held by swapper/0/1: #0: (&type->s_umount_key#13/1){+.+.+.}, at: [<c011e84c>] sget+0x248/0x574 stack backtrace: rpc_wait_bit_killable __wait_on_bit out_of_line_wait_on_bit __rpc_execute rpc_run_task rpc_call_sync nfs_proc_get_root nfs_get_root nfs_fs_mount_common nfs_try_mount nfs_fs_mount mount_fs vfs_kern_mount do_mount sys_mount do_mount_root mount_root prepare_namespace kernel_init_freeable kernel_init Although the rootfs mounts, the system is unstable. Here's a transcript from a PM test: http://www.pwsan.com/omap/testlogs/test_v3.9-rc3/20130317194234/pm/37xxevm/37xxevm_log.txt Here's what the test log should look like: http://www.pwsan.com/omap/testlogs/test_v3.8/20130218214403/pm/37xxevm/37xxevm_log.txt Mailing list discussion is here: http://lkml.org/lkml/2013/3/4/221 Deal with this for v3.9 by reverting the problem commit, until folks can figure out the right long-term course of action. Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Mandeep Singh Baines <msb@chromium.org> Cc: Jeff Layton <jlayton@redhat.com> Cc: Shawn Guo <shawn.guo@linaro.org> Cc: <maciej.rutecki@gmail.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ben Chan <benchan@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit b81ea1b (PM / QoS: Fix concurrency issues and memory leaks in device PM QoS) put calls to pm_qos_sysfs_add_latency(), pm_qos_sysfs_add_flags(), pm_qos_sysfs_remove_latency(), and pm_qos_sysfs_remove_flags() under dev_pm_qos_mtx, which was a mistake, because it may lead to deadlocks in some situations. For example, if pm_qos_remote_wakeup_store() is run in parallel with dev_pm_qos_constraints_destroy(), they may deadlock in the following way: ====================================================== [ INFO: possible circular locking dependency detected ] 3.9.0-rc4-next-20130328-sasha-00014-g91a3267 #319 Tainted: G W ------------------------------------------------------- trinity-child6/12371 is trying to acquire lock: (s_active#54){++++.+}, at: [<ffffffff81301631>] sysfs_addrm_finish+0x31/0x60 but task is already holding lock: (dev_pm_qos_mtx){+.+.+.}, at: [<ffffffff81f07cc3>] dev_pm_qos_constraints_destroy+0x23/0x250 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (dev_pm_qos_mtx){+.+.+.}: [<ffffffff811811da>] lock_acquire+0x1aa/0x240 [<ffffffff83dab809>] __mutex_lock_common+0x59/0x5e0 [<ffffffff83dabebf>] mutex_lock_nested+0x3f/0x50 [<ffffffff81f07f2f>] dev_pm_qos_update_flags+0x3f/0xc0 [<ffffffff81f05f4f>] pm_qos_remote_wakeup_store+0x3f/0x70 [<ffffffff81efbb43>] dev_attr_store+0x13/0x20 [<ffffffff812ffdaa>] sysfs_write_file+0xfa/0x150 [<ffffffff8127f2c1>] __kernel_write+0x81/0x150 [<ffffffff812afc2d>] write_pipe_buf+0x4d/0x80 [<ffffffff812af57c>] splice_from_pipe_feed+0x7c/0x120 [<ffffffff812afa25>] __splice_from_pipe+0x45/0x80 [<ffffffff812b14fc>] splice_from_pipe+0x4c/0x70 [<ffffffff812b1538>] default_file_splice_write+0x18/0x30 [<ffffffff812afae3>] do_splice_from+0x83/0xb0 [<ffffffff812afb2e>] direct_splice_actor+0x1e/0x20 [<ffffffff812b0277>] splice_direct_to_actor+0xe7/0x200 [<ffffffff812b15bc>] do_splice_direct+0x4c/0x70 [<ffffffff8127eda9>] do_sendfile+0x169/0x300 [<ffffffff8127ff94>] SyS_sendfile64+0x64/0xb0 [<ffffffff83db7d18>] tracesys+0xe1/0xe6 -> #0 (s_active#54){++++.+}: [<ffffffff811800cf>] __lock_acquire+0x15bf/0x1e50 [<ffffffff811811da>] lock_acquire+0x1aa/0x240 [<ffffffff81300aa2>] sysfs_deactivate+0x122/0x1a0 [<ffffffff81301631>] sysfs_addrm_finish+0x31/0x60 [<ffffffff812ff77f>] sysfs_hash_and_remove+0x7f/0xb0 [<ffffffff813035a1>] sysfs_unmerge_group+0x51/0x70 [<ffffffff81f068f4>] pm_qos_sysfs_remove_flags+0x14/0x20 [<ffffffff81f07490>] __dev_pm_qos_hide_flags+0x30/0x70 [<ffffffff81f07cd5>] dev_pm_qos_constraints_destroy+0x35/0x250 [<ffffffff81f06931>] dpm_sysfs_remove+0x11/0x50 [<ffffffff81efcf6f>] device_del+0x3f/0x1b0 [<ffffffff81efd128>] device_unregister+0x48/0x60 [<ffffffff82d4083c>] usb_hub_remove_port_device+0x1c/0x20 [<ffffffff82d2a9cd>] hub_disconnect+0xdd/0x160 [<ffffffff82d36ab7>] usb_unbind_interface+0x67/0x170 [<ffffffff81f001a7>] __device_release_driver+0x87/0xe0 [<ffffffff81f00559>] device_release_driver+0x29/0x40 [<ffffffff81effc58>] bus_remove_device+0x148/0x160 [<ffffffff81efd07f>] device_del+0x14f/0x1b0 [<ffffffff82d344f9>] usb_disable_device+0xf9/0x280 [<ffffffff82d34ff8>] usb_set_configuration+0x268/0x840 [<ffffffff82d3a7fc>] usb_remove_store+0x4c/0x80 [<ffffffff81efbb43>] dev_attr_store+0x13/0x20 [<ffffffff812ffdaa>] sysfs_write_file+0xfa/0x150 [<ffffffff8127f71d>] do_loop_readv_writev+0x4d/0x90 [<ffffffff8127f999>] do_readv_writev+0xf9/0x1e0 [<ffffffff8127faba>] vfs_writev+0x3a/0x60 [<ffffffff8127fc60>] SyS_writev+0x50/0xd0 [<ffffffff83db7d18>] tracesys+0xe1/0xe6 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(dev_pm_qos_mtx); lock(s_active#54); lock(dev_pm_qos_mtx); lock(s_active#54); *** DEADLOCK *** To avoid that, remove the calls to functions mentioned above from under dev_pm_qos_mtx and introduce a separate lock to prevent races between functions that add or remove device PM QoS sysfs attributes from happening. Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Check for the presence of the '/cpus' OF node before dereferencing it blindly: [ 4.181793] Unable to handle kernel NULL pointer dereference at virtual address 0000001c [ 4.181793] pgd = c0004000 [ 4.181823] [0000001c] *pgd=00000000 [ 4.181823] Internal error: Oops: 5 [#1] SMP ARM [ 4.181823] Modules linked in: [ 4.181823] CPU: 1 Tainted: G W (3.8.0-15-generic #25~hbankD) [ 4.181854] PC is at of_get_next_child+0x64/0x70 [ 4.181854] LR is at of_get_next_child+0x24/0x70 [ 4.181854] pc : [<c04fda18>] lr : [<c04fd9d8>] psr: 60000113 [ 4.181854] sp : ed891ec0 ip : ed891ec0 fp : ed891ed4 [ 4.181884] r10: c04dafd0 r9 : c098690c r8 : c0936208 [ 4.181884] r7 : ed890000 r6 : c0a63d00 r5 : 00000000 r4 : 00000000 [ 4.181884] r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : c0b2acc8 [ 4.181884] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 4.181884] Control: 10c5387d Table: adcb804a DAC: 00000015 [ 4.181915] Process swapper/0 (pid: 1, stack limit = 0xed890238) [ 4.181915] Stack: (0xed891ec0 to 0xed892000) [ 4.181915] 1ec0: c09b7b70 00000007 ed891efc ed891ed8 c04daff4 c04fd9c0 00000000 c09b7b70 [ 4.181915] 1ee0: 00000007 c0a63d00 ed890000 c0936208 ed891f54 ed891f00 c00088e0 c04dafdc [ 4.181945] 1f00: ed891f54 ed891f10 c006e940 00000000 00000000 00000007 00000007 c08a4914 [ 4.181945] 1f20: 00000000 c07dbd30 c0a63d00 c09b7b70 00000007 c0a63d00 000000bc c0936208 [ 4.181945] 1f40: c098690c c0986914 ed891f94 ed891f58 c0936a40 c00087bc 00000007 00000007 [ 4.181976] 1f60: c0936208 be8bda20 b6eea010 c0a63d00 c064547c 00000000 00000000 00000000 [ 4.181976] 1f80: 00000000 00000000 ed891fac ed891f98 c0645498 c09368c8 00000000 00000000 [ 4.181976] 1fa0: 00000000 ed891fb0 c0014658 c0645488 00000000 00000000 00000000 00000000 [ 4.182006] 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 4.182006] 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 [ 4.182037] [<c04fda18>] (of_get_next_child+0x64/0x70) from [<c04daff4>] (cpu0_cpufreq_driver_init+0x24/0x284) [ 4.182067] [<c04daff4>] (cpu0_cpufreq_driver_init+0x24/0x284) from [<c00088e0>] (do_one_initcall+0x130/0x1b0) [ 4.182067] [<c00088e0>] (do_one_initcall+0x130/0x1b0) from [<c0936a40>] (kernel_init_freeable+0x184/0x24c) [ 4.182098] [<c0936a40>] (kernel_init_freeable+0x184/0x24c) from [<c0645498>] (kernel_init+0x1c/0xf4) [ 4.182128] [<c0645498>] (kernel_init+0x1c/0xf4) from [<c0014658>] (ret_from_fork+0x14/0x20) [ 4.182128] Code: f57ff04f e320f004 e89da830 e89da830 (e595001c) [ 4.182128] ---[ end trace 634903a22e8609cb ]--- [ 4.182189] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b [ 4.182189] [ 4.642395] CPU0: stopping [rjw: Changelog] Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The sched_clock_remote() implementation has the following inatomicity problem on 32bit systems when accessing the remote scd->clock, which is a 64bit value. CPU0 CPU1 sched_clock_local() sched_clock_remote(CPU0) ... remote_clock = scd[CPU0]->clock read_low32bit(scd[CPU0]->clock) cmpxchg64(scd->clock,...) read_high32bit(scd[CPU0]->clock) While the update of scd->clock is using an atomic64 mechanism, the readout on the remote cpu is not, which can cause completely bogus readouts. It is a quite rare problem, because it requires the update to hit the narrow race window between the low/high readout and the update must go across the 32bit boundary. The resulting misbehaviour is, that CPU1 will see the sched_clock on CPU1 ~4 seconds ahead of it's own and update CPU1s sched_clock value to this bogus timestamp. This stays that way due to the clamping implementation for about 4 seconds until the synchronization with CLOCK_MONOTONIC undoes the problem. The issue is hard to observe, because it might only result in a less accurate SCHED_OTHER timeslicing behaviour. To create observable damage on realtime scheduling classes, it is necessary that the bogus update of CPU1 sched_clock happens in the context of an realtime thread, which then gets charged 4 seconds of RT runtime, which results in the RT throttler mechanism to trigger and prevent scheduling of RT tasks for a little less than 4 seconds. So this is quite unlikely as well. The issue was quite hard to decode as the reproduction time is between 2 days and 3 weeks and intrusive tracing makes it less likely, but the following trace recorded with trace_clock=global, which uses sched_clock_local(), gave the final hint: <idle>-0 0d..30 400269.477150: hrtimer_cancel: hrtimer=0xf7061e80 <idle>-0 0d..30 400269.477151: hrtimer_start: hrtimer=0xf7061e80 ... irq/20-S-587 1d..32 400273.772118: sched_wakeup: comm= ... target_cpu=0 <idle>-0 0dN.30 400273.772118: hrtimer_cancel: hrtimer=0xf7061e80 What happens is that CPU0 goes idle and invokes sched_clock_idle_sleep_event() which invokes sched_clock_local() and CPU1 runs a remote wakeup for CPU0 at the same time, which invokes sched_remote_clock(). The time jump gets propagated to CPU0 via sched_remote_clock() and stays stale on both cores for ~4 seconds. There are only two other possibilities, which could cause a stale sched clock: 1) ktime_get() which reads out CLOCK_MONOTONIC returns a sporadic wrong value. 2) sched_clock() which reads the TSC returns a sporadic wrong value. #1 can be excluded because sched_clock would continue to increase for one jiffy and then go stale. #2 can be excluded because it would not make the clock jump forward. It would just result in a stale sched_clock for one jiffy. After quite some brain twisting and finding the same pattern on other traces, sched_clock_remote() remained the only place which could cause such a problem and as explained above it's indeed racy on 32bit systems. So while on 64bit systems the readout is atomic, we need to verify the remote readout on 32bit machines. We need to protect the local->clock readout in sched_clock_remote() on 32bit as well because an NMI could hit between the low and the high readout, call sched_clock_local() and modify local->clock. Thanks to Siegfried Wulsch for bearing with my debug requests and going through the tedious tasks of running a bunch of reproducer systems to generate the debug information which let me decode the issue. Reported-by: Siegfried Wulsch <Siegfried.Wulsch@rovema.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1304051544160.21884@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org

The function tracing control loop used by perf spits out a warning if the called function is not a control function. This is because the control function references a per cpu allocated data structure on struct ftrace_ops that is not allocated for other types of functions. commit 0a01640 "ftrace: Optimize the function tracer list loop" Had an optimization done to all function tracing loops to optimize for a single registered ops. Unfortunately, this allows for a slight race when tracing starts or ends, where the stub function might be called after the current registered ops is removed. In this case we get the following dump: root# perf stat -e ftrace:function sleep 1 [ 74.339105] WARNING: at include/linux/ftrace.h:209 ftrace_ops_control_func+0xde/0xf0() [ 74.349522] Hardware name: PRIMERGY RX200 S6 [ 74.357149] Modules linked in: sg igb iTCO_wdt ptp pps_core iTCO_vendor_support i7core_edac dca lpc_ich i2c_i801 coretemp edac_core crc32c_intel mfd_core ghash_clmulni_intel dm_multipath acpi_power_meter pcspk r microcode vhost_net tun macvtap macvlan nfsd kvm_intel kvm auth_rpcgss nfs_acl lockd sunrpc uinput xfs libcrc32c sd_mod crc_t10dif sr_mod cdrom mgag200 i2c_algo_bit drm_kms_helper ttm qla2xxx mptsas ahci drm li bahci scsi_transport_sas mptscsih libata scsi_transport_fc i2c_core mptbase scsi_tgt dm_mirror dm_region_hash dm_log dm_mod [ 74.446233] Pid: 1377, comm: perf Tainted: G W 3.9.0-rc1 #1 [ 74.453458] Call Trace: [ 74.456233] [<ffffffff81062e3f>] warn_slowpath_common+0x7f/0xc0 [ 74.462997] [<ffffffff810fbc60>] ? rcu_note_context_switch+0xa0/0xa0 [ 74.470272] [<ffffffff811041a2>] ? __unregister_ftrace_function+0xa2/0x1a0 [ 74.478117] [<ffffffff81062e9a>] warn_slowpath_null+0x1a/0x20 [ 74.484681] [<ffffffff81102ede>] ftrace_ops_control_func+0xde/0xf0 [ 74.491760] [<ffffffff8162f400>] ftrace_call+0x5/0x2f [ 74.497511] [<ffffffff8162f400>] ? ftrace_call+0x5/0x2f [ 74.503486] [<ffffffff8162f400>] ? ftrace_call+0x5/0x2f [ 74.509500] [<ffffffff810fbc65>] ? synchronize_sched+0x5/0x50 [ 74.516088] [<ffffffff816254d5>] ? _cond_resched+0x5/0x40 [ 74.522268] [<ffffffff810fbc65>] ? synchronize_sched+0x5/0x50 [ 74.528837] [<ffffffff811041a2>] ? __unregister_ftrace_function+0xa2/0x1a0 [ 74.536696] [<ffffffff816254d5>] ? _cond_resched+0x5/0x40 [ 74.542878] [<ffffffff8162402d>] ? mutex_lock+0x1d/0x50 [ 74.548869] [<ffffffff81105c67>] unregister_ftrace_function+0x27/0x50 [ 74.556243] [<ffffffff8111eadf>] perf_ftrace_event_register+0x9f/0x140 [ 74.563709] [<ffffffff816254d5>] ? _cond_resched+0x5/0x40 [ 74.569887] [<ffffffff8162402d>] ? mutex_lock+0x1d/0x50 [ 74.575898] [<ffffffff8111e94e>] perf_trace_destroy+0x2e/0x50 [ 74.582505] [<ffffffff81127ba9>] tp_perf_event_destroy+0x9/0x10 [ 74.589298] [<ffffffff811295d0>] free_event+0x70/0x1a0 [ 74.595208] [<ffffffff8112a579>] perf_event_release_kernel+0x69/0xa0 [ 74.602460] [<ffffffff816254d5>] ? _cond_resched+0x5/0x40 [ 74.608667] [<ffffffff8112a640>] put_event+0x90/0xc0 [ 74.614373] [<ffffffff8112a740>] perf_release+0x10/0x20 [ 74.620367] [<ffffffff811a3044>] __fput+0xf4/0x280 [ 74.625894] [<ffffffff811a31de>] ____fput+0xe/0x10 [ 74.631387] [<ffffffff81083697>] task_work_run+0xa7/0xe0 [ 74.637452] [<ffffffff81014981>] do_notify_resume+0x71/0xb0 [ 74.643843] [<ffffffff8162fa92>] int_signal+0x12/0x17 To fix this a new ftrace_ops flag is added that denotes the ftrace_list_end ftrace_ops stub as just that, a stub. This flag is now checked in the control loop and the function is not called if the flag is set. Thanks to Jovi for not just reporting the bug, but also pointing out where the bug was in the code. Link: http://lkml.kernel.org/r/514A8855.7090402@redhat.com Link: http://lkml.kernel.org/r/1364377499-1900-15-git-send-email-jovi.zhangwei@huawei.com Tested-by: WANG Chao <chaowang@redhat.com> Reported-by: WANG Chao <chaowang@redhat.com> Reported-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

do_loopback calls lock_mount(path) and forget to unlock_mount if clone_mnt or copy_mnt fails. [ 77.661566] ================================================ [ 77.662939] [ BUG: lock held when returning to user space! ] [ 77.664104] 3.9.0-rc5+ #17 Not tainted [ 77.664982] ------------------------------------------------ [ 77.666488] mount/514 is leaving the kernel with locks still held! [ 77.668027] 2 locks held by mount/514: [ 77.668817] #0: (&sb->s_type->i_mutex_key#7){+.+.+.}, at: [<ffffffff811cca22>] lock_mount+0x32/0xe0 [ 77.671755] #1: (&namespace_sem){+++++.}, at: [<ffffffff811cca3a>] lock_mount+0x4a/0xe0 Signed-off-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

In paravirtualized x86_64 kernels, vmalloc_fault may cause an oops when lazy MMU updates are enabled, because set_pgd effects are being deferred. One instance of this problem is during process mm cleanup with memory cgroups enabled. The chain of events is as follows: - zap_pte_range enables lazy MMU updates - zap_pte_range eventually calls mem_cgroup_charge_statistics, which accesses the vmalloc'd mem_cgroup per-cpu stat area - vmalloc_fault is triggered which tries to sync the corresponding PGD entry with set_pgd, but the update is deferred - vmalloc_fault oopses due to a mismatch in the PUD entries The OOPs usually looks as so: ------------[ cut here ]------------ kernel BUG at arch/x86/mm/fault.c:396! invalid opcode: 0000 [#1] SMP .. snip .. CPU 1 Pid: 10866, comm: httpd Not tainted 3.6.10-4.fc18.x86_64 #1 RIP: e030:[<ffffffff816271bf>] [<ffffffff816271bf>] vmalloc_fault+0x11f/0x208 .. snip .. Call Trace: [<ffffffff81627759>] do_page_fault+0x399/0x4b0 [<ffffffff81004f4c>] ? xen_mc_extend_args+0xec/0x110 [<ffffffff81624065>] page_fault+0x25/0x30 [<ffffffff81184d03>] ? mem_cgroup_charge_statistics.isra.13+0x13/0x50 [<ffffffff81186f78>] __mem_cgroup_uncharge_common+0xd8/0x350 [<ffffffff8118aac7>] mem_cgroup_uncharge_page+0x57/0x60 [<ffffffff8115fbc0>] page_remove_rmap+0xe0/0x150 [<ffffffff8115311a>] ? vm_normal_page+0x1a/0x80 [<ffffffff81153e61>] unmap_single_vma+0x531/0x870 [<ffffffff81154962>] unmap_vmas+0x52/0xa0 [<ffffffff81007442>] ? pte_mfn_to_pfn+0x72/0x100 [<ffffffff8115c8f8>] exit_mmap+0x98/0x170 [<ffffffff810050d9>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e [<ffffffff81059ce3>] mmput+0x83/0xf0 [<ffffffff810624c4>] exit_mm+0x104/0x130 [<ffffffff8106264a>] do_exit+0x15a/0x8c0 [<ffffffff810630ff>] do_group_exit+0x3f/0xa0 [<ffffffff81063177>] sys_exit_group+0x17/0x20 [<ffffffff8162bae9>] system_call_fastpath+0x16/0x1b Calling arch_flush_lazy_mmu_mode immediately after set_pgd makes the changes visible to the consistency checks. Cc: <stable@vger.kernel.org> RedHat-Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=914737 Tested-by: Josh Boyer <jwboyer@redhat.com> Reported-and-Tested-by: Krishna Raman <kraman@redhat.com> Signed-off-by: Samu Kallio <samu.kallio@aberdeencloud.com> Link: http://lkml.kernel.org/r/1364045796-10720-1-git-send-email-konrad.wilk@oracle.com Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

e100 uses pci_map_single, but fails to check for a dma mapping error after its use, resulting in a stack trace: [ 46.656594] ------------[ cut here ]------------ [ 46.657004] WARNING: at lib/dma-debug.c:933 check_unmap+0x47b/0x950() [ 46.657004] Hardware name: To Be Filled By O.E.M. [ 46.657004] e100 0000:00:0e.0: DMA-API: device driver failed to check map error[device address=0x000000007a4540fa] [size=90 bytes] [mapped as single] [ 46.657004] Modules linked in: [ 46.657004] w83627hf hwmon_vid snd_via82xx ppdev snd_ac97_codec ac97_bus snd_seq snd_pcm snd_mpu401 snd_mpu401_uart ns558 snd_rawmidi gameport parport_pc e100 snd_seq_device parport snd_page_alloc snd_timer snd soundcore skge shpchp k8temp mii edac_core i2c_viapro edac_mce_amd nfsd auth_rpcgss nfs_acl lockd sunrpc binfmt_misc uinput ata_generic pata_acpi radeon i2c_algo_bit drm_kms_helper ttm firewire_ohci drm firewire_core pata_via sata_via i2c_core sata_promise crc_itu_t [ 46.657004] Pid: 792, comm: ip Not tainted 3.8.0-0.rc6.git0.1.fc19.x86_64 #1 [ 46.657004] Call Trace: [ 46.657004] <IRQ> [<ffffffff81065ed0>] warn_slowpath_common+0x70/0xa0 [ 46.657004] [<ffffffff81065f4c>] warn_slowpath_fmt+0x4c/0x50 [ 46.657004] [<ffffffff81364cfb>] check_unmap+0x47b/0x950 [ 46.657004] [<ffffffff8136522f>] debug_dma_unmap_page+0x5f/0x70 [ 46.657004] [<ffffffffa030f0f0>] ? e100_tx_clean+0x30/0x210 [e100] [ 46.657004] [<ffffffffa030f1a8>] e100_tx_clean+0xe8/0x210 [e100] [ 46.657004] [<ffffffffa030fc6f>] e100_poll+0x56f/0x6c0 [e100] [ 46.657004] [<ffffffff8159dce1>] ? net_rx_action+0xa1/0x370 [ 46.657004] [<ffffffff8159ddb2>] net_rx_action+0x172/0x370 [ 46.657004] [<ffffffff810703bf>] __do_softirq+0xef/0x3d0 [ 46.657004] [<ffffffff816e4ebc>] call_softirq+0x1c/0x30 [ 46.657004] [<ffffffff8101c485>] do_softirq+0x85/0xc0 [ 46.657004] [<ffffffff81070885>] irq_exit+0xd5/0xe0 [ 46.657004] [<ffffffff816e5756>] do_IRQ+0x56/0xc0 [ 46.657004] [<ffffffff816dacb2>] common_interrupt+0x72/0x72 [ 46.657004] <EOI> [<ffffffff816da1eb>] ? _raw_spin_unlock_irqrestore+0x3b/0x70 [ 46.657004] [<ffffffff816d124d>] __slab_free+0x58/0x38b [ 46.657004] [<ffffffff81214424>] ? fsnotify_clear_marks_by_inode+0x34/0x120 [ 46.657004] [<ffffffff811b0417>] ? kmem_cache_free+0x97/0x320 [ 46.657004] [<ffffffff8157fc14>] ? sock_destroy_inode+0x34/0x40 [ 46.657004] [<ffffffff8157fc14>] ? sock_destroy_inode+0x34/0x40 [ 46.657004] [<ffffffff811b0692>] kmem_cache_free+0x312/0x320 [ 46.657004] [<ffffffff8157fc14>] sock_destroy_inode+0x34/0x40 [ 46.657004] [<ffffffff811e8c28>] destroy_inode+0x38/0x60 [ 46.657004] [<ffffffff811e8d5e>] evict+0x10e/0x1a0 [ 46.657004] [<ffffffff811e9605>] iput+0xf5/0x180 [ 46.657004] [<ffffffff811e4338>] dput+0x248/0x310 [ 46.657004] [<ffffffff811ce0e1>] __fput+0x171/0x240 [ 46.657004] [<ffffffff811ce26e>] ____fput+0xe/0x10 [ 46.657004] [<ffffffff8108d54c>] task_work_run+0xac/0xe0 [ 46.657004] [<ffffffff8106c6ed>] do_exit+0x26d/0xc30 [ 46.657004] [<ffffffff8109eccc>] ? finish_task_switch+0x7c/0x120 [ 46.657004] [<ffffffff816dad58>] ? retint_swapgs+0x13/0x1b [ 46.657004] [<ffffffff8106d139>] do_group_exit+0x49/0xc0 [ 46.657004] [<ffffffff8106d1c4>] sys_exit_group+0x14/0x20 [ 46.657004] [<ffffffff816e3b19>] system_call_fastpath+0x16/0x1b [ 46.657004] ---[ end trace 4468c44e2156e7d1 ]--- [ 46.657004] Mapped at: [ 46.657004] [<ffffffff813663d1>] debug_dma_map_page+0x91/0x140 [ 46.657004] [<ffffffffa030e8eb>] e100_xmit_prepare+0x12b/0x1c0 [e100] [ 46.657004] [<ffffffffa030c924>] e100_exec_cb+0x84/0x140 [e100] [ 46.657004] [<ffffffffa030e56a>] e100_xmit_frame+0x3a/0x190 [e100] [ 46.657004] [<ffffffff8159ee89>] dev_hard_start_xmit+0x259/0x6c0 Easy fix, modify the cb paramter to e100_exec_cb to return an error, and do the dma_mapping_error check in the obvious place This was reported previously here: http://article.gmane.org/gmane.linux.network/257893 But nobody stepped up and fixed it. CC: Josh Boyer <jwboyer@redhat.com> CC: e1000-devel@lists.sourceforge.net Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Michal Jaegermann <michal@harddata.com> Tested-by: Aaron Brown <aaron.f.brown@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>

This patch attempts to fix: https://bugzilla.kernel.org/show_bug.cgi?id=56461 The symptom is a crash and messages like this: chrome: Corrupted page table at address 34a03000 *pdpt = 0000000000000000 *pde = 0000000000000000 Bad pagetable: 000f [#1] PREEMPT SMP Ingo guesses this got introduced by commit 611ae8e ("x86/tlb: enable tlb flush range support for x86") since that code started to free unused pagetables. On x86-32 PAE kernels, that new code has the potential to free an entire PMD page and will clear one of the four page-directory-pointer-table (aka pgd_t entries). The hardware aggressively "caches" these top-level entries and invlpg does not actually affect the CPU's copy. If we clear one we *HAVE* to do a full TLB flush, otherwise we might continue using a freed pmd page. (note, we do this properly on the population side in pud_populate()). This patch tracks whenever we clear one of these entries in the 'struct mmu_gather', and ensures that we follow up with a full tlb flush. BTW, I disassembled and checked that: if (tlb->fullmm == 0) and if (!tlb->fullmm && !tlb->need_flush_all) generate essentially the same code, so there should be zero impact there to the !PAE case. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Artem S Tashkinov <t.artem@mailcity.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Currently IOP3XX_PERIPHERAL_VIRT_BASE conflicts with PCI_IO_VIRT_BASE: address size PCI_IO_VIRT_BASE 0xfee00000 0x200000 IOP3XX_PERIPHERAL_VIRT_BASE 0xfeffe000 0x2000 Fix by moving IOP3XX_PERIPHERAL_VIRT_BASE below PCI_IO_VIRT_BASE. The patch fixes the following kernel panic with 3.9-rc1 on iop3xx boards: [ 0.000000] Booting Linux on physical CPU 0x0 [ 0.000000] Initializing cgroup subsys cpu [ 0.000000] Linux version 3.9.0-rc1-iop32x (aaro@blackmetal) (gcc version 4.7.2 (GCC) ) #20 PREEMPT Tue Mar 5 16:44:36 EET 2013 [ 0.000000] bootconsole [earlycon0] enabled [ 0.000000] ------------[ cut here ]------------ [ 0.000000] kernel BUG at mm/vmalloc.c:1145! [ 0.000000] Internal error: Oops - BUG: 0 [#1] PREEMPT ARM [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 Not tainted (3.9.0-rc1-iop32x #20) [ 0.000000] PC is at vm_area_add_early+0x4c/0x88 [ 0.000000] LR is at add_static_vm_early+0x14/0x68 [ 0.000000] pc : [<c03e74a8>] lr : [<c03e1c40>] psr: 800000d3 [ 0.000000] sp : c03ffee4 ip : dfffdf88 fp : c03ffef4 [ 0.000000] r10: 00000002 r9 : 000000cf r8 : 00000653 [ 0.000000] r7 : c040eca8 r6 : c03e2408 r5 : dfffdf60 r4 : 00200000 [ 0.000000] r3 : dfffdfd8 r2 : feffe000 r1 : ff000000 r0 : dfffdf60 [ 0.000000] Flags: Nzcv IRQs off FIQs off Mode SVC_32 ISA ARM Segment kernel [ 0.000000] Control: 0000397f Table: a0004000 DAC: 00000017 [ 0.000000] Process swapper (pid: 0, stack limit = 0xc03fe1b8) [ 0.000000] Stack: (0xc03ffee4 to 0xc0400000) [ 0.000000] fee0: 00200000 c03fff0c c03ffef8 c03e1c40 c03e7468 00200000 fee00000 [ 0.000000] ff00: c03fff2c c03fff10 c03e23e4 c03e1c38 feffe000 c0408ee4 ff000000 c0408f04 [ 0.000000] ff20: c03fff3c c03fff30 c03e2434 c03e23b4 c03fff84 c03fff40 c03e2c94 c03e2414 [ 0.000000] ff40: c03f8878 c03f6410 ffff0000 000bffff 00001000 00000008 c03fff84 c03f6410 [ 0.000000] ff60: c04227e8 c03fffd4 a0008000 c03f8878 69052e30 c02f96eb c03fffbc c03fff88 [ 0.000000] ff80: c03e044c c03e268c 00000000 0000397f c0385130 00000001 ffffffff c03f8874 [ 0.000000] ffa0: dfffffff a0004000 69052e30 a03f61a0 c03ffff4 c03fffc0 c03dd5cc c03e0184 [ 0.000000] ffc0: 00000000 00000000 00000000 00000000 00000000 c03f8878 0000397d c040601c [ 0.000000] ffe0: c03f8874 c0408674 00000000 c03ffff8 a0008040 c03dd558 00000000 00000000 [ 0.000000] Backtrace: [ 0.000000] [<c03e745c>] (vm_area_add_early+0x0/0x88) from [<c03e1c40>] (add_static_vm_early+0x14/0x68) Tested-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The following RCU splat indicates lack of RCU protection: [ 953.267649] =============================== [ 953.267652] [ INFO: suspicious RCU usage. ] [ 953.267657] 3.9.0-0.rc6.git2.4.fc19.ppc64p7 #1 Not tainted [ 953.267661] ------------------------------- [ 953.267664] include/linux/cgroup.h:534 suspicious rcu_dereference_check() usage! [ 953.267669] [ 953.267669] other info that might help us debug this: [ 953.267669] [ 953.267675] [ 953.267675] rcu_scheduler_active = 1, debug_locks = 0 [ 953.267680] 1 lock held by glxgears/1289: [ 953.267683] #0: (&sig->cred_guard_mutex){+.+.+.}, at: [<c00000000027f884>] .prepare_bprm_creds+0x34/0xa0 [ 953.267700] [ 953.267700] stack backtrace: [ 953.267704] Call Trace: [ 953.267709] [c0000001f0d1b6e0] [c000000000016e30] .show_stack+0x130/0x200 (unreliable) [ 953.267717] [c0000001f0d1b7b0] [c0000000001267f8] .lockdep_rcu_suspicious+0x138/0x180 [ 953.267724] [c0000001f0d1b840] [c0000000001d43a4] .perf_event_comm+0x4c4/0x690 [ 953.267731] [c0000001f0d1b950] [c00000000027f6e4] .set_task_comm+0x84/0x1f0 [ 953.267737] [c0000001f0d1b9f0] [c000000000280414] .setup_new_exec+0x94/0x220 [ 953.267744] [c0000001f0d1ba70] [c0000000002f665c] .load_elf_binary+0x58c/0x19b0 ... This commit therefore adds the required RCU read-side critical section to perf_event_comm(). Reported-by: Adam Jackson <ajax@redhat.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: a.p.zijlstra@chello.nl Cc: paulus@samba.org Cc: acme@ghostprotocols.net Link: http://lkml.kernel.org/r/20130419190124.GA8638@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Tested-by: Gustavo Luiz Duarte <gusld@br.ibm.com>

commit eb20ff9 upstream. With deferred setup for SCO, it is possible that userspace closes the socket when it is in the BT_CONNECT2 state, after the Connect Request is received but before the Accept Synchonous Connection is sent. If this happens the following crash was observed, when the connection is terminated: [ +0.000003] hci_sync_conn_complete_evt: hci0 status 0x10 [ +0.000005] sco_connect_cfm: hcon ffff88003d1bd800 bdaddr 40:98:4e:32:d7:39 status 16 [ +0.000003] sco_conn_del: hcon ffff88003d1bd800 conn ffff88003cc8e300, err 110 [ +0.000015] BUG: unable to handle kernel NULL pointer dereference at 0000000000000199 [ +0.000906] IP: [<ffffffff810620dd>] __lock_acquire+0xed/0xe82 [ +0.000000] PGD 3d21f067 PUD 3d291067 PMD 0 [ +0.000000] Oops: 0002 [#1] SMP [ +0.000000] Modules linked in: rfcomm bnep btusb bluetooth [ +0.000000] CPU 0 [ +0.000000] Pid: 1481, comm: kworker/u:2H Not tainted 3.9.0-rc1-25019-gad82cdd #1 Bochs Bochs [ +0.000000] RIP: 0010:[<ffffffff810620dd>] [<ffffffff810620dd>] __lock_acquire+0xed/0xe82 [ +0.000000] RSP: 0018:ffff88003c3c19d8 EFLAGS: 00010002 [ +0.000000] RAX: 0000000000000001 RBX: 0000000000000246 RCX: 0000000000000000 [ +0.000000] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88003d1be868 [ +0.000000] RBP: ffff88003c3c1a98 R08: 0000000000000002 R09: 0000000000000000 [ +0.000000] R10: ffff88003d1be868 R11: ffff88003e20b000 R12: 0000000000000002 [ +0.000000] R13: ffff88003aaa8000 R14: 000000000000006e R15: ffff88003d1be850 [ +0.000000] FS: 0000000000000000(0000) GS:ffff88003e200000(0000) knlGS:0000000000000000 [ +0.000000] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ +0.000000] CR2: 0000000000000199 CR3: 000000003c1cb000 CR4: 00000000000006b0 [ +0.000000] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ +0.000000] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ +0.000000] Process kworker/u:2H (pid: 1481, threadinfo ffff88003c3c0000, task ffff88003aaa8000) [ +0.000000] Stack: [ +0.000000] ffffffff81b16342 0000000000000000 0000000000000000 ffff88003d1be868 [ +0.000000] ffffffff00000000 00018c0c7863e367 000000003c3c1a28 ffffffff8101efbd [ +0.000000] 0000000000000000 ffff88003e3d2400 ffff88003c3c1a38 ffffffff81007c7a [ +0.000000] Call Trace: [ +0.000000] [<ffffffff8101efbd>] ? kvm_clock_read+0x34/0x3b [ +0.000000] [<ffffffff81007c7a>] ? paravirt_sched_clock+0x9/0xd [ +0.000000] [<ffffffff81007fd4>] ? sched_clock+0x9/0xb [ +0.000000] [<ffffffff8104fd7a>] ? sched_clock_local+0x12/0x75 [ +0.000000] [<ffffffff810632d1>] lock_acquire+0x93/0xb1 [ +0.000000] [<ffffffffa0022339>] ? spin_lock+0x9/0xb [bluetooth] [ +0.000000] [<ffffffff8105f3d8>] ? lock_release_holdtime.part.22+0x4e/0x55 [ +0.000000] [<ffffffff814f6038>] _raw_spin_lock+0x40/0x74 [ +0.000000] [<ffffffffa0022339>] ? spin_lock+0x9/0xb [bluetooth] [ +0.000000] [<ffffffff814f6936>] ? _raw_spin_unlock+0x23/0x36 [ +0.000000] [<ffffffffa0022339>] spin_lock+0x9/0xb [bluetooth] [ +0.000000] [<ffffffffa00230cc>] sco_conn_del+0x76/0xbb [bluetooth] [ +0.000000] [<ffffffffa002391d>] sco_connect_cfm+0x2da/0x2e9 [bluetooth] [ +0.000000] [<ffffffffa000862a>] hci_proto_connect_cfm+0x38/0x65 [bluetooth] [ +0.000000] [<ffffffffa0008d30>] hci_sync_conn_complete_evt.isra.79+0x11a/0x13e [bluetooth] [ +0.000000] [<ffffffffa000cd96>] hci_event_packet+0x153b/0x239d [bluetooth] [ +0.000000] [<ffffffff814f68ff>] ? _raw_spin_unlock_irqrestore+0x48/0x5c [ +0.000000] [<ffffffffa00025f6>] hci_rx_work+0xf3/0x2e3 [bluetooth] [ +0.000000] [<ffffffff8103efed>] process_one_work+0x1dc/0x30b [ +0.000000] [<ffffffff8103ef83>] ? process_one_work+0x172/0x30b [ +0.000000] [<ffffffff8103e07f>] ? spin_lock_irq+0x9/0xb [ +0.000000] [<ffffffff8103fc8d>] worker_thread+0x123/0x1d2 [ +0.000000] [<ffffffff8103fb6a>] ? manage_workers+0x240/0x240 [ +0.000000] [<ffffffff81044211>] kthread+0x9d/0xa5 [ +0.000000] [<ffffffff81044174>] ? __kthread_parkme+0x60/0x60 [ +0.000000] [<ffffffff814f75bc>] ret_from_fork+0x7c/0xb0 [ +0.000000] [<ffffffff81044174>] ? __kthread_parkme+0x60/0x60 [ +0.000000] Code: d7 44 89 8d 50 ff ff ff 4c 89 95 58 ff ff ff e8 44 fc ff ff 44 8b 8d 50 ff ff ff 48 85 c0 4c 8b 95 58 ff ff ff 0f 84 7a 04 00 00 <f0> ff 80 98 01 00 00 83 3d 25 41 a7 00 00 45 8b b5 e8 05 00 00 [ +0.000000] RIP [<ffffffff810620dd>] __lock_acquire+0xed/0xe82 [ +0.000000] RSP <ffff88003c3c19d8> [ +0.000000] CR2: 0000000000000199 [ +0.000000] ---[ end trace e73cd3b52352dd34 ]--- Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org> Tested-by: Frederic Dalleau <frederic.dalleau@intel.com> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 7fc0357 upstream. The following issue was reported. WARNING: at net/mac80211/util.c:599 ieee80211_can_queue_work.isra.7+0x32/0x40 [mac80211]() Hardware name: iMac12,1 queueing ieee80211 work while going to suspend Pid: 0, comm: swapper/0 Tainted: PF O 3.8.2-206.fc18.x86_64 #1 Call Trace: Mar 16 09:39:17 Parags-iMac kernel: [ 3993.642992] <IRQ> [<ffffffff8105e61f>] warn_slowpath_common+0x7f/0xc0 [<ffffffffa0581420>] ? ath_start_rx_poll+0x70/0x70 [ath9k] <ffffffff8105e716>] warn_slowpath_fmt+0x46/0x50 [<ffffffffa045b542>] ieee80211_can_queue_work.isra.7+0x32/0x40 Fix this by avoiding to queue the work if our device has already been marked as suspended or stopped. Reported-by: Parag Warudkar <parag.lkml@gmail.com> Tested-by: Parag Warudkar <parag.lkml@gmail.com> Signed-off-by: Luis R. Rodriguez <mcgrof@do-not-panic.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit ff931c8 upstream. clk inits on OMAP happen quite early, even before slab is available. The dependency comes from the fact that the timer init code starts to use clocks and hwmod and we need clocks to be initialized by then. There are various problems doing clk inits this early, one is, not being able to do dynamic clk registrations and hence the dependency on clk-private.h. The other is, inability to debug early kernel crashes without enabling DEBUG_LL and earlyprintk. Doing early clk init also exposed another instance of a kernel panic due to a BUG() when CONFIG_DEBUG_SLAB is enabled. [ 0.000000] Kernel BUG at c01174f8 [verbose debug info unavailable] [ 0.000000] Internal error: Oops - BUG: 0 [#1] SMP ARM [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 Not tainted (3.9.0-rc1-12179-g72d48f9 #6) [ 0.000000] PC is at __kmalloc+0x1d4/0x248 [ 0.000000] LR is at __clk_init+0x2e0/0x364 [ 0.000000] pc : [<c01174f8>] lr : [<c0441f54>] psr: 600001d3 [ 0.000000] sp : c076ff28 ip : c065cefc fp : c0441f54 [ 0.000000] r10: 0000001c r9 : 000080d0 r8 : c076ffd4 [ 0.000000] r7 : c074b578 r6 : c0794d88 r5 : 00000040 r4 : 00000000 [ 0.000000] r3 : 00000000 r2 : c07cac70 r1 : 000080d0 r0 : 0000001c [ 0.000000] Flags: nZCv IRQs off FIQs off Mode SVC_32 ISA ARM Segment kernel [ 0.000000] Control: 10c53c7d Table: 8000404a DAC: 00000017 [ 0.000000] Process swapper (pid: 0, stack limit = 0xc076e240) [ 0.000000] Stack: (0xc076ff28 to 0xc0770000) [ 0.000000] ff20: 22222222 c0794ec8 c06546e8 00000000 00000040 c0794d88 [ 0.000000] ff40: c074b578 c076ffd4 c07951c8 c076e000 00000000 c0441f54 c074b578 c076ffd4 [ 0.000000] ff60: c0793828 00000040 c0794d88 c074b578 c076ffd4 c0776900 c076e000 c07272ac [ 0.000000] ff80: 2f800000 c074c968 c07f93d0 c0719780 c076ffa0 c076ff98 00000000 00000000 [ 0.000000] ffa0: 00000000 00000000 00000000 00000001 c074cd6c c077b1ec 8000406a c0715724 [ 0.000000] ffc0: 00000000 00000000 00000000 00000000 00000000 c074c968 10c53c7d c0776974 [ 0.000000] ffe0: c074cd6c c077b1ec 8000406a 411fc092 00000000 80008074 00000000 00000000 [ 0.000000] [<c01174f8>] (__kmalloc+0x1d4/0x248) from [<c0441f54>] (__clk_init+0x2e0/0x364) [ 0.000000] [<c0441f54>] (__clk_init+0x2e0/0x364) from [<c07272ac>] (omap4xxx_clk_init+0xbc/0x140) [ 0.000000] [<c07272ac>] (omap4xxx_clk_init+0xbc/0x140) from [<c0719780>] (setup_arch+0x15c/0x284) [ 0.000000] [<c0719780>] (setup_arch+0x15c/0x284) from [<c0715724>] (start_kernel+0x7c/0x334) [ 0.000000] [<c0715724>] (start_kernel+0x7c/0x334) from [<80008074>] (0x80008074) [ 0.000000] Code: e5883004 e1a00006 e28dd00c e8bd8ff0 (e7f001f2) [ 0.000000] ---[ end trace 1b75b31a2719ed1c ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! It was a know issue, that slab allocations would fail when common clock core tries to cache parent pointers for mux clocks on OMAP, and hence a patch 'clk: Allow late cache allocation for clk->parents, commit 7975059' was added to work this problem around. A BUG() within kmalloc() with CONFIG_DEBUG_SLAB enabled was completely overlooked causing this regression. More details on the issue reported can be found here, http://www.mail-archive.com/linux-omap@vger.kernel.org/msg85932.html With all these issues around clk inits happening way too early, it makes sense to at least move them to a point where dynamic memory allocations are possible. So move them to a point just before the timer code starts using clocks and hwmod. This should at least pave way for clk inits on OMAP moving to dynamic clock registrations instead of using the static macros defined in clk-private.h. The issue with kernel panic while CONFIG_DEBUG_SLAB is enabled was reported by Piotr Haber and Tony Lindgren and this patch fixes the reported issue as well. Reported-by: Piotr Haber <phaber@broadcom.com> Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Rajendra Nayak <rnayak@ti.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Reviewed-by: Mike Turquette <mturquette@linaro.org> Acked-by: Paul Walmsley <paul@pwsan.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 1de14c3 upstream. This patch attempts to fix: https://bugzilla.kernel.org/show_bug.cgi?id=56461 The symptom is a crash and messages like this: chrome: Corrupted page table at address 34a03000 *pdpt = 0000000000000000 *pde = 0000000000000000 Bad pagetable: 000f [#1] PREEMPT SMP Ingo guesses this got introduced by commit 611ae8e ("x86/tlb: enable tlb flush range support for x86") since that code started to free unused pagetables. On x86-32 PAE kernels, that new code has the potential to free an entire PMD page and will clear one of the four page-directory-pointer-table (aka pgd_t entries). The hardware aggressively "caches" these top-level entries and invlpg does not actually affect the CPU's copy. If we clear one we *HAVE* to do a full TLB flush, otherwise we might continue using a freed pmd page. (note, we do this properly on the population side in pud_populate()). This patch tracks whenever we clear one of these entries in the 'struct mmu_gather', and ensures that we follow up with a full tlb flush. BTW, I disassembled and checked that: if (tlb->fullmm == 0) and if (!tlb->fullmm && !tlb->need_flush_all) generate essentially the same code, so there should be zero impact there to the !PAE case. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Artem S Tashkinov <t.artem@mailcity.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit a1cbcaa upstream. The sched_clock_remote() implementation has the following inatomicity problem on 32bit systems when accessing the remote scd->clock, which is a 64bit value. CPU0 CPU1 sched_clock_local() sched_clock_remote(CPU0) ... remote_clock = scd[CPU0]->clock read_low32bit(scd[CPU0]->clock) cmpxchg64(scd->clock,...) read_high32bit(scd[CPU0]->clock) While the update of scd->clock is using an atomic64 mechanism, the readout on the remote cpu is not, which can cause completely bogus readouts. It is a quite rare problem, because it requires the update to hit the narrow race window between the low/high readout and the update must go across the 32bit boundary. The resulting misbehaviour is, that CPU1 will see the sched_clock on CPU1 ~4 seconds ahead of it's own and update CPU1s sched_clock value to this bogus timestamp. This stays that way due to the clamping implementation for about 4 seconds until the synchronization with CLOCK_MONOTONIC undoes the problem. The issue is hard to observe, because it might only result in a less accurate SCHED_OTHER timeslicing behaviour. To create observable damage on realtime scheduling classes, it is necessary that the bogus update of CPU1 sched_clock happens in the context of an realtime thread, which then gets charged 4 seconds of RT runtime, which results in the RT throttler mechanism to trigger and prevent scheduling of RT tasks for a little less than 4 seconds. So this is quite unlikely as well. The issue was quite hard to decode as the reproduction time is between 2 days and 3 weeks and intrusive tracing makes it less likely, but the following trace recorded with trace_clock=global, which uses sched_clock_local(), gave the final hint: <idle>-0 0d..30 400269.477150: hrtimer_cancel: hrtimer=0xf7061e80 <idle>-0 0d..30 400269.477151: hrtimer_start: hrtimer=0xf7061e80 ... irq/20-S-587 1d..32 400273.772118: sched_wakeup: comm= ... target_cpu=0 <idle>-0 0dN.30 400273.772118: hrtimer_cancel: hrtimer=0xf7061e80 What happens is that CPU0 goes idle and invokes sched_clock_idle_sleep_event() which invokes sched_clock_local() and CPU1 runs a remote wakeup for CPU0 at the same time, which invokes sched_remote_clock(). The time jump gets propagated to CPU0 via sched_remote_clock() and stays stale on both cores for ~4 seconds. There are only two other possibilities, which could cause a stale sched clock: 1) ktime_get() which reads out CLOCK_MONOTONIC returns a sporadic wrong value. 2) sched_clock() which reads the TSC returns a sporadic wrong value. #1 can be excluded because sched_clock would continue to increase for one jiffy and then go stale. #2 can be excluded because it would not make the clock jump forward. It would just result in a stale sched_clock for one jiffy. After quite some brain twisting and finding the same pattern on other traces, sched_clock_remote() remained the only place which could cause such a problem and as explained above it's indeed racy on 32bit systems. So while on 64bit systems the readout is atomic, we need to verify the remote readout on 32bit machines. We need to protect the local->clock readout in sched_clock_remote() on 32bit as well because an NMI could hit between the low and the high readout, call sched_clock_local() and modify local->clock. Thanks to Siegfried Wulsch for bearing with my debug requests and going through the tedious tasks of running a bunch of reproducer systems to generate the debug information which let me decode the issue. Reported-by: Siegfried Wulsch <Siegfried.Wulsch@rovema.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1304051544160.21884@ionos Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 1160c27 upstream. In paravirtualized x86_64 kernels, vmalloc_fault may cause an oops when lazy MMU updates are enabled, because set_pgd effects are being deferred. One instance of this problem is during process mm cleanup with memory cgroups enabled. The chain of events is as follows: - zap_pte_range enables lazy MMU updates - zap_pte_range eventually calls mem_cgroup_charge_statistics, which accesses the vmalloc'd mem_cgroup per-cpu stat area - vmalloc_fault is triggered which tries to sync the corresponding PGD entry with set_pgd, but the update is deferred - vmalloc_fault oopses due to a mismatch in the PUD entries The OOPs usually looks as so: ------------[ cut here ]------------ kernel BUG at arch/x86/mm/fault.c:396! invalid opcode: 0000 [#1] SMP .. snip .. CPU 1 Pid: 10866, comm: httpd Not tainted 3.6.10-4.fc18.x86_64 #1 RIP: e030:[<ffffffff816271bf>] [<ffffffff816271bf>] vmalloc_fault+0x11f/0x208 .. snip .. Call Trace: [<ffffffff81627759>] do_page_fault+0x399/0x4b0 [<ffffffff81004f4c>] ? xen_mc_extend_args+0xec/0x110 [<ffffffff81624065>] page_fault+0x25/0x30 [<ffffffff81184d03>] ? mem_cgroup_charge_statistics.isra.13+0x13/0x50 [<ffffffff81186f78>] __mem_cgroup_uncharge_common+0xd8/0x350 [<ffffffff8118aac7>] mem_cgroup_uncharge_page+0x57/0x60 [<ffffffff8115fbc0>] page_remove_rmap+0xe0/0x150 [<ffffffff8115311a>] ? vm_normal_page+0x1a/0x80 [<ffffffff81153e61>] unmap_single_vma+0x531/0x870 [<ffffffff81154962>] unmap_vmas+0x52/0xa0 [<ffffffff81007442>] ? pte_mfn_to_pfn+0x72/0x100 [<ffffffff8115c8f8>] exit_mmap+0x98/0x170 [<ffffffff810050d9>] ? __raw_callee_save_xen_pmd_val+0x11/0x1e [<ffffffff81059ce3>] mmput+0x83/0xf0 [<ffffffff810624c4>] exit_mm+0x104/0x130 [<ffffffff8106264a>] do_exit+0x15a/0x8c0 [<ffffffff810630ff>] do_group_exit+0x3f/0xa0 [<ffffffff81063177>] sys_exit_group+0x17/0x20 [<ffffffff8162bae9>] system_call_fastpath+0x16/0x1b Calling arch_flush_lazy_mmu_mode immediately after set_pgd makes the changes visible to the consistency checks. RedHat-Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=914737 Tested-by: Josh Boyer <jwboyer@redhat.com> Reported-and-Tested-by: Krishna Raman <kraman@redhat.com> Signed-off-by: Samu Kallio <samu.kallio@aberdeencloud.com> Link: http://lkml.kernel.org/r/1364045796-10720-1-git-send-email-konrad.wilk@oracle.com Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 852e4a8 upstream. Since commit 89c8d91 ("tty: localise the lock") I see a dead lock in one of my dummy_hcd + g_nokia test cases. The first run was usually okay, the second often resulted in a splat by lockdep and the third was usually a dead lock. Lockdep complained about tty->hangup_work and tty->legacy_mutex taken both ways: | ====================================================== | [ INFO: possible circular locking dependency detected ] | 3.7.0-rc6+ #204 Not tainted | ------------------------------------------------------- | kworker/2:1/35 is trying to acquire lock: | (&tty->legacy_mutex){+.+.+.}, at: [<c14051e6>] tty_lock_nested+0x36/0x80 | | but task is already holding lock: | ((&tty->hangup_work)){+.+...}, at: [<c104f6e4>] process_one_work+0x124/0x5e0 | | which lock already depends on the new lock. | | the existing dependency chain (in reverse order) is: | | -> #2 ((&tty->hangup_work)){+.+...}: | [<c107fe74>] lock_acquire+0x84/0x190 | [<c104d82d>] flush_work+0x3d/0x240 | [<c12e6986>] tty_ldisc_flush_works+0x16/0x30 | [<c12e7861>] tty_ldisc_release+0x21/0x70 | [<c12e0dfc>] tty_release+0x35c/0x470 | [<c1105e28>] __fput+0xd8/0x270 | [<c1105fcd>] ____fput+0xd/0x10 | [<c1051dd9>] task_work_run+0xb9/0xf0 | [<c1002a51>] do_notify_resume+0x51/0x80 | [<c140550a>] work_notifysig+0x35/0x3b | | -> #1 (&tty->legacy_mutex/1){+.+...}: | [<c107fe74>] lock_acquire+0x84/0x190 | [<c140276c>] mutex_lock_nested+0x6c/0x2f0 | [<c14051e6>] tty_lock_nested+0x36/0x80 | [<c1405279>] tty_lock_pair+0x29/0x70 | [<c12e0bb8>] tty_release+0x118/0x470 | [<c1105e28>] __fput+0xd8/0x270 | [<c1105fcd>] ____fput+0xd/0x10 | [<c1051dd9>] task_work_run+0xb9/0xf0 | [<c1002a51>] do_notify_resume+0x51/0x80 | [<c140550a>] work_notifysig+0x35/0x3b | | -> #0 (&tty->legacy_mutex){+.+.+.}: | [<c107f3c9>] __lock_acquire+0x1189/0x16a0 | [<c107fe74>] lock_acquire+0x84/0x190 | [<c140276c>] mutex_lock_nested+0x6c/0x2f0 | [<c14051e6>] tty_lock_nested+0x36/0x80 | [<c140523f>] tty_lock+0xf/0x20 | [<c12df8e4>] __tty_hangup+0x54/0x410 | [<c12dfcb2>] do_tty_hangup+0x12/0x20 | [<c104f763>] process_one_work+0x1a3/0x5e0 | [<c104fec9>] worker_thread+0x119/0x3a0 | [<c1055084>] kthread+0x94/0xa0 | [<c140ca37>] ret_from_kernel_thread+0x1b/0x28 | |other info that might help us debug this: | |Chain exists of: | &tty->legacy_mutex --> &tty->legacy_mutex/1 --> (&tty->hangup_work) | | Possible unsafe locking scenario: | | CPU0 CPU1 | ---- ---- | lock((&tty->hangup_work)); | lock(&tty->legacy_mutex/1); | lock((&tty->hangup_work)); | lock(&tty->legacy_mutex); | | *** DEADLOCK *** Before the path mentioned tty_ldisc_release() look like this: | tty_ldisc_halt(tty); | tty_ldisc_flush_works(tty); | tty_lock(); As it can be seen, it first flushes the workqueue and then grabs the tty_lock. Now we grab the lock first: | tty_lock_pair(tty, o_tty); | tty_ldisc_halt(tty); | tty_ldisc_flush_works(tty); so lockdep's complaint seems valid. The earlier version of this patch took the ldisc_mutex since the other user of tty_ldisc_flush_works() (tty_set_ldisc()) did this. Peter Hurley then said that it is should not be requried. Since it wasn't done earlier, I dropped this part. The code under tty_ldisc_kill() was executed earlier with the tty lock taken so it is taken again. I was able to reproduce the deadlock on v3.8-rc1, this patch fixes the problem in my testcase. I didn't notice any problems so far. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Alan Cox <alan@linux.intel.com> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Bryan O'Donoghue <bryan.odonoghue.lkml@nexus-software.ie> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

syzbot reported the following crash [1] Issue came with the blamed commit. Instead of going through all the iov components, we keep using the first one and end up with a malformed skb. [1] kernel BUG at net/core/skbuff.c:2849 ! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 0 UID: 0 PID: 6230 Comm: syz-executor132 Not tainted 6.13.0-rc1-syzkaller-00407-g96b6fcc0ee41 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 RIP: 0010:__pskb_pull_tail+0x1568/0x1570 net/core/skbuff.c:2848 Code: 38 c1 0f 8c 32 f1 ff ff 4c 89 f7 e8 92 96 74 f8 e9 25 f1 ff ff e8 e8 ae 09 f8 48 8b 5c 24 08 e9 eb fb ff ff e8 d9 ae 09 f8 90 <0f> 0b 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90004cbef30 EFLAGS: 00010293 RAX: ffffffff8995c347 RBX: 00000000fffffff2 RCX: ffff88802cf45a00 RDX: 0000000000000000 RSI: 00000000fffffff2 RDI: 0000000000000000 RBP: ffff88807df0c06a R08: ffffffff8995b084 R09: 1ffff1100fbe185c R10: dffffc0000000000 R11: ffffed100fbe185d R12: ffff888076e85d50 R13: ffff888076e85c80 R14: ffff888076e85cf4 R15: ffff888076e85c80 FS: 00007f0dca6ea6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0dca6ead58 CR3: 00000000119da000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> skb_cow_data+0x2da/0xcb0 net/core/skbuff.c:5284 tipc_aead_decrypt net/tipc/crypto.c:894 [inline] tipc_crypto_rcv+0x402/0x24e0 net/tipc/crypto.c:1844 tipc_rcv+0x57e/0x12a0 net/tipc/node.c:2109 tipc_l2_rcv_msg+0x2bd/0x450 net/tipc/bearer.c:668 __netif_receive_skb_list_ptype net/core/dev.c:5720 [inline] __netif_receive_skb_list_core+0x8b7/0x980 net/core/dev.c:5762 __netif_receive_skb_list net/core/dev.c:5814 [inline] netif_receive_skb_list_internal+0xa51/0xe30 net/core/dev.c:5905 gro_normal_list include/net/gro.h:515 [inline] napi_complete_done+0x2b5/0x870 net/core/dev.c:6256 napi_complete include/linux/netdevice.h:567 [inline] tun_get_user+0x2ea0/0x4890 drivers/net/tun.c:1982 tun_chr_write_iter+0x10d/0x1f0 drivers/net/tun.c:2057 do_iter_readv_writev+0x600/0x880 vfs_writev+0x376/0xba0 fs/read_write.c:1050 do_writev+0x1b6/0x360 fs/read_write.c:1096 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: de4f5fe ("iov_iter: add iter_iovec() helper") Reported-by: syzbot+4f66250f6663c0c1d67e@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/675b61aa.050a0220.599f4.00bb.GAE@google.com/T/#u Cc: stable@vger.kernel.org Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Joe Damato <jdamato@fastly.com> Reviewed-by: Jens Axboe <axboe@kernel.dk> Acked-by: Willem de Bruijn <willemb@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://patch.msgid.link/20241212222247.724674-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

link down work may be scheduled before lgr freed but execute after lgr freed, which may result in crash. So it is need to hold a reference before shedule link down work, and put the reference after work executed or canceled. The relevant crash call stack as follows: list_del corruption. prev->next should be ffffb638c9c0fe20, but was 0000000000000000 ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:51! invalid opcode: 0000 [#1] SMP NOPTI CPU: 6 PID: 978112 Comm: kworker/6:119 Kdump: loaded Tainted: G #1 Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 2221b89 04/01/2014 Workqueue: events smc_link_down_work [smc] RIP: 0010:__list_del_entry_valid.cold+0x31/0x47 RSP: 0018:ffffb638c9c0fdd8 EFLAGS: 00010086 RAX: 0000000000000054 RBX: ffff942fb75e5128 RCX: 0000000000000000 RDX: ffff943520930aa0 RSI: ffff94352091fc80 RDI: ffff94352091fc80 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffb638c9c0fc38 R10: ffffb638c9c0fc30 R11: ffffffffa015eb28 R12: 0000000000000002 R13: ffffb638c9c0fe20 R14: 0000000000000001 R15: ffff942f9cd051c0 FS: 0000000000000000(0000) GS:ffff943520900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4f25214000 CR3: 000000025fbae004 CR4: 00000000007706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: rwsem_down_write_slowpath+0x17e/0x470 smc_link_down_work+0x3c/0x60 [smc] process_one_work+0x1ac/0x350 worker_thread+0x49/0x2f0 ? rescuer_thread+0x360/0x360 kthread+0x118/0x140 ? __kthread_bind_mask+0x60/0x60 ret_from_fork+0x1f/0x30 Fixes: 541afa1 ("net/smc: add smcr_port_err() and smcr_link_down() processing") Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com> Reviewed-by: Tony Lu <tonylu@linux.alibaba.com> Signed-off-by: David S. Miller <davem@davemloft.net>

…e flex array The following UBSAN error is reported during boot on the db410c board on a clang-19 build: Internal error: UBSAN: array index out of bounds: 00000000f2005512 [#1] PREEMPT SMP ... pc : qnoc_probe+0x5f8/0x5fc ... The cause of the error is that the counter member was not set before accessing the annotated flexible array member, but after that. Fix this by initializing it earlier. Reported-by: Linux Kernel Functional Testing <lkft@linaro.org> Closes: https://lore.kernel.org/r/CA+G9fYs+2mBz1y2dAzxkj9-oiBJ2Acm1Sf1h2YQ3VmBqj_VX2g@mail.gmail.com Fixes: dd4904f ("interconnect: qcom: Annotate struct icc_onecell_data with __counted_by") Reviewed-by: Nathan Chancellor <nathan@kernel.org> Link: https://lore.kernel.org/r/20241203223334.233404-1-djakov@kernel.org Signed-off-by: Georgi Djakov <djakov@kernel.org>

syzkaller reported recursion with a loop of three calls (netfs_rreq_assess, netfs_retry_reads and netfs_rreq_terminated) hitting the limit of the stack during an unbuffered or direct I/O read. There are a number of issues: (1) There is no limit on the number of retries. (2) A subrequest is supposed to be abandoned if it does not transfer anything (NETFS_SREQ_NO_PROGRESS), but that isn't checked under all circumstances. (3) The actual root cause, which is this: if (atomic_dec_and_test(&rreq->nr_outstanding)) netfs_rreq_terminated(rreq, ...); When we do a retry, we bump the rreq->nr_outstanding counter to prevent the final cleanup phase running before we've finished dispatching the retries. The problem is if we hit 0, we have to do the cleanup phase - but we're in the cleanup phase and end up repeating the retry cycle, hence the recursion. Work around the problem by limiting the number of retries. This is based on Lizhi Xu's patch[1], and makes the following changes: (1) Replace NETFS_SREQ_NO_PROGRESS with NETFS_SREQ_MADE_PROGRESS and make the filesystem set it if it managed to read or write at least one byte of data. Clear this bit before issuing a subrequest. (2) Add a ->retry_count member to the subrequest and increment it any time we do a retry. (3) Remove the NETFS_SREQ_RETRYING flag as it is superfluous with ->retry_count. If the latter is non-zero, we're doing a retry. (4) Abandon a subrequest if retry_count is non-zero and we made no progress. (5) Use ->retry_count in both the write-side and the read-size. [?] Question: Should I set a hard limit on retry_count in both read and write? Say it hits 50, we always abandon it. The problem is that these changes only mitigate the issue. As long as it made at least one byte of progress, the recursion is still an issue. This patch mitigates the problem, but does not fix the underlying cause. I have patches that will do that, but it's an intrusive fix that's currently pending for the next merge window. The oops generated by KASAN looks something like: BUG: TASK stack guard page was hit at ffffc9000482ff48 (stack is ffffc90004830000..ffffc90004838000) Oops: stack guard page: 0000 [#1] PREEMPT SMP KASAN NOPTI ... RIP: 0010:mark_lock+0x25/0xc60 kernel/locking/lockdep.c:4686 ... mark_usage kernel/locking/lockdep.c:4646 [inline] __lock_acquire+0x906/0x3ce0 kernel/locking/lockdep.c:5156 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ___slab_alloc+0x123/0x1880 mm/slub.c:3695 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3908 __slab_alloc_node mm/slub.c:3961 [inline] slab_alloc_node mm/slub.c:4122 [inline] kmem_cache_alloc_noprof+0x2a7/0x2f0 mm/slub.c:4141 radix_tree_node_alloc.constprop.0+0x1e8/0x350 lib/radix-tree.c:253 idr_get_free+0x528/0xa40 lib/radix-tree.c:1506 idr_alloc_u32+0x191/0x2f0 lib/idr.c:46 idr_alloc+0xc1/0x130 lib/idr.c:87 p9_tag_alloc+0x394/0x870 net/9p/client.c:321 p9_client_prepare_req+0x19f/0x4d0 net/9p/client.c:644 p9_client_zc_rpc.constprop.0+0x105/0x880 net/9p/client.c:793 p9_client_read_once+0x443/0x820 net/9p/client.c:1570 p9_client_read+0x13f/0x1b0 net/9p/client.c:1534 v9fs_issue_read+0x115/0x310 fs/9p/vfs_addr.c:74 netfs_retry_read_subrequests fs/netfs/read_retry.c:60 [inline] netfs_retry_reads+0x153a/0x1d00 fs/netfs/read_retry.c:232 netfs_rreq_assess+0x5d3/0x870 fs/netfs/read_collect.c:371 netfs_rreq_terminated+0xe5/0x110 fs/netfs/read_collect.c:407 netfs_retry_reads+0x155e/0x1d00 fs/netfs/read_retry.c:235 netfs_rreq_assess+0x5d3/0x870 fs/netfs/read_collect.c:371 netfs_rreq_terminated+0xe5/0x110 fs/netfs/read_collect.c:407 netfs_retry_reads+0x155e/0x1d00 fs/netfs/read_retry.c:235 netfs_rreq_assess+0x5d3/0x870 fs/netfs/read_collect.c:371 ... netfs_rreq_terminated+0xe5/0x110 fs/netfs/read_collect.c:407 netfs_retry_reads+0x155e/0x1d00 fs/netfs/read_retry.c:235 netfs_rreq_assess+0x5d3/0x870 fs/netfs/read_collect.c:371 netfs_rreq_terminated+0xe5/0x110 fs/netfs/read_collect.c:407 netfs_retry_reads+0x155e/0x1d00 fs/netfs/read_retry.c:235 netfs_rreq_assess+0x5d3/0x870 fs/netfs/read_collect.c:371 netfs_rreq_terminated+0xe5/0x110 fs/netfs/read_collect.c:407 netfs_dispatch_unbuffered_reads fs/netfs/direct_read.c:103 [inline] netfs_unbuffered_read fs/netfs/direct_read.c:127 [inline] netfs_unbuffered_read_iter_locked+0x12f6/0x19b0 fs/netfs/direct_read.c:221 netfs_unbuffered_read_iter+0xc5/0x100 fs/netfs/direct_read.c:256 v9fs_file_read_iter+0xbf/0x100 fs/9p/vfs_file.c:361 do_iter_readv_writev+0x614/0x7f0 fs/read_write.c:832 vfs_readv+0x4cf/0x890 fs/read_write.c:1025 do_preadv fs/read_write.c:1142 [inline] __do_sys_preadv fs/read_write.c:1192 [inline] __se_sys_preadv fs/read_write.c:1187 [inline] __x64_sys_preadv+0x22d/0x310 fs/read_write.c:1187 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 Fixes: ee4cdf7 ("netfs: Speed up buffered reading") Closes: https://syzkaller.appspot.com/bug?extid=1fc6f64c40a9d143cfb6 Signed-off-by: David Howells <dhowells@redhat.com> Link: https://lore.kernel.org/r/20241108034020.3695718-1-lizhi.xu@windriver.com/ [1] Link: https://lore.kernel.org/r/20241213135013.2964079-9-dhowells@redhat.com Tested-by: syzbot+885c03ad650731743489@syzkaller.appspotmail.com Suggested-by: Lizhi Xu <lizhi.xu@windriver.com> cc: Dominique Martinet <asmadeus@codewreck.org> cc: Jeff Layton <jlayton@kernel.org> cc: v9fs@lists.linux.dev cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Reported-by: syzbot+885c03ad650731743489@syzkaller.appspotmail.com Signed-off-by: Christian Brauner <brauner@kernel.org>

Google Juniper and other Chromebook platforms have a very old bootloader which populates /firmware node without proper address/size-cells leading to warnings: Missing '#address-cells' in /firmware WARNING: CPU: 0 PID: 1 at drivers/of/base.c:106 of_bus_n_addr_cells+0x90/0xf0 Modules linked in: CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.0 #1 933ab9971ff4d5dc58cb378a96f64c7f72e3454d Hardware name: Google juniper sku16 board (DT) ... Missing '#size-cells' in /firmware WARNING: CPU: 0 PID: 1 at drivers/of/base.c:133 of_bus_n_size_cells+0x90/0xf0 Modules linked in: CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G W 6.12.0 #1 933ab9971ff4d5dc58cb378a96f64c7f72e3454d Tainted: [W]=WARN Hardware name: Google juniper sku16 board (DT) These platform won't receive updated bootloader/firmware, so add an exclusion for platforms with a "coreboot" compatible node. While this is wider than necessary, that's the easiest fix and it doesn't doesn't matter if we miss checking other platforms using coreboot. We may revisit this later and address with a fixup to the DT itself. Reported-by: Sasha Levin <sashal@kernel.org> Closes: https://lore.kernel.org/all/Z0NUdoG17EwuCigT@sashalap/ Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Chen-Yu Tsai <wenst@chromium.org> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Signed-off-by: Rob Herring (Arm) <robh@kernel.org>

The tcpci_irq() may meet below NULL pointer dereference issue: [ 2.641851] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010 [ 2.641951] status 0x1, 0x37f [ 2.650659] Mem abort info: [ 2.656490] ESR = 0x0000000096000004 [ 2.660230] EC = 0x25: DABT (current EL), IL = 32 bits [ 2.665532] SET = 0, FnV = 0 [ 2.668579] EA = 0, S1PTW = 0 [ 2.671715] FSC = 0x04: level 0 translation fault [ 2.676584] Data abort info: [ 2.679459] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 2.684936] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 2.689980] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 2.695284] [0000000000000010] user address but active_mm is swapper [ 2.701632] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 2.707883] Modules linked in: [ 2.710936] CPU: 1 UID: 0 PID: 87 Comm: irq/111-2-0051 Not tainted 6.12.0-rc6-06316-g7f63786ad3d1-dirty #4 [ 2.720570] Hardware name: NXP i.MX93 11X11 EVK board (DT) [ 2.726040] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 2.732989] pc : tcpci_irq+0x38/0x318 [ 2.736647] lr : _tcpci_irq+0x14/0x20 [ 2.740295] sp : ffff80008324bd30 [ 2.743597] x29: ffff80008324bd70 x28: ffff800080107894 x27: ffff800082198f70 [ 2.750721] x26: ffff0000050e6680 x25: ffff000004d172ac x24: ffff0000050f0000 [ 2.757845] x23: ffff000004d17200 x22: 0000000000000001 x21: ffff0000050f0000 [ 2.764969] x20: ffff000004d17200 x19: 0000000000000000 x18: 0000000000000001 [ 2.772093] x17: 0000000000000000 x16: ffff80008183d8a0 x15: ffff00007fbab040 [ 2.779217] x14: ffff00007fb918c0 x13: 0000000000000000 x12: 000000000000017a [ 2.786341] x11: 0000000000000001 x10: 0000000000000a90 x9 : ffff80008324bd00 [ 2.793465] x8 : ffff0000050f0af0 x7 : ffff00007fbaa840 x6 : 0000000000000031 [ 2.800589] x5 : 000000000000017a x4 : 0000000000000002 x3 : 0000000000000002 [ 2.807713] x2 : ffff80008324bd3a x1 : 0000000000000010 x0 : 0000000000000000 [ 2.814838] Call trace: [ 2.817273] tcpci_irq+0x38/0x318 [ 2.820583] _tcpci_irq+0x14/0x20 [ 2.823885] irq_thread_fn+0x2c/0xa8 [ 2.827456] irq_thread+0x16c/0x2f4 [ 2.830940] kthread+0x110/0x114 [ 2.834164] ret_from_fork+0x10/0x20 [ 2.837738] Code: f9426420 f9001fe0 d2800000 52800201 (f9400a60) This may happen on shared irq case. Such as two Type-C ports share one irq. After the first port finished tcpci_register_port(), it may trigger interrupt. However, if the interrupt comes by chance the 2nd port finishes devm_request_threaded_irq(), the 2nd port interrupt handler will run at first. Then the above issue happens due to tcpci is still a NULL pointer in tcpci_irq() when dereference to regmap. devm_request_threaded_irq() <-- port1 irq comes disable_irq(client->irq); tcpci_register_port() This will restore the logic to the state before commit (77e8510 "usb: typec: tcpci: support edge irq"). However, moving tcpci_register_port() earlier creates a problem when use edge irq because tcpci_init() will be called before devm_request_threaded_irq(). The tcpci_init() writes the ALERT_MASK to the hardware to tell it to start generating interrupts but we're not ready to deal with them yet, then the ALERT events may be missed and ALERT line will not recover to high level forever. To avoid the issue, this will also set ALERT_MASK register after devm_request_threaded_irq() return. Fixes: 77e8510 ("usb: typec: tcpci: support edge irq") Cc: stable <stable@kernel.org> Tested-by: Emanuele Ghidoli <emanuele.ghidoli@toradex.com> Signed-off-by: Xu Yang <xu.yang_2@nxp.com> Reviewed-by: Francesco Dolcini <francesco.dolcini@toradex.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org> Link: https://lore.kernel.org/r/20241218095328.2604607-1-xu.yang_2@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

When we call btrfs_read_folio() to bring a folio uptodate, we unlock the folio. The result of that is that a different thread can modify the mapping (like remove it with invalidate) before we call folio_lock(). This results in an invalid page and we need to try again. In particular, if we are relocating concurrently with aborting a transaction, this can result in a crash like the following: BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 76 PID: 1411631 Comm: kworker/u322:5 Workqueue: events_unbound btrfs_reclaim_bgs_work RIP: 0010:set_page_extent_mapped+0x20/0xb0 RSP: 0018:ffffc900516a7be8 EFLAGS: 00010246 RAX: ffffea009e851d08 RBX: ffffea009e0b1880 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffc900516a7b90 RDI: ffffea009e0b1880 RBP: 0000000003573000 R08: 0000000000000001 R09: ffff88c07fd2f3f0 R10: 0000000000000000 R11: 0000194754b575be R12: 0000000003572000 R13: 0000000003572fff R14: 0000000000100cca R15: 0000000005582fff FS: 0000000000000000(0000) GS:ffff88c07fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000407d00f002 CR4: 00000000007706f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> ? __die+0x78/0xc0 ? page_fault_oops+0x2a8/0x3a0 ? __switch_to+0x133/0x530 ? wq_worker_running+0xa/0x40 ? exc_page_fault+0x63/0x130 ? asm_exc_page_fault+0x22/0x30 ? set_page_extent_mapped+0x20/0xb0 relocate_file_extent_cluster+0x1a7/0x940 relocate_data_extent+0xaf/0x120 relocate_block_group+0x20f/0x480 btrfs_relocate_block_group+0x152/0x320 btrfs_relocate_chunk+0x3d/0x120 btrfs_reclaim_bgs_work+0x2ae/0x4e0 process_scheduled_works+0x184/0x370 worker_thread+0xc6/0x3e0 ? blk_add_timer+0xb0/0xb0 kthread+0xae/0xe0 ? flush_tlb_kernel_range+0x90/0x90 ret_from_fork+0x2f/0x40 ? flush_tlb_kernel_range+0x90/0x90 ret_from_fork_asm+0x11/0x20 </TASK> This occurs because cleanup_one_transaction() calls destroy_delalloc_inodes() which calls invalidate_inode_pages2() which takes the folio_lock before setting mapping to NULL. We fail to check this, and subsequently call set_extent_mapping(), which assumes that mapping != NULL (in fact it asserts that in debug mode) Note that the "fixes" patch here is not the one that introduced the race (the very first iteration of this code from 2009) but a more recent change that made this particular crash happen in practice. Fixes: e7f1326 ("btrfs: set page extent mapped after read_folio in relocate_one_page") CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com>

Access to genmask field in struct nft_set_ext results in unaligned atomic read: [ 72.130109] Unable to handle kernel paging request at virtual address ffff0000c2bb708c [ 72.131036] Mem abort info: [ 72.131213] ESR = 0x0000000096000021 [ 72.131446] EC = 0x25: DABT (current EL), IL = 32 bits [ 72.132209] SET = 0, FnV = 0 [ 72.133216] EA = 0, S1PTW = 0 [ 72.134080] FSC = 0x21: alignment fault [ 72.135593] Data abort info: [ 72.137194] ISV = 0, ISS = 0x00000021, ISS2 = 0x00000000 [ 72.142351] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 72.145989] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 72.150115] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000237d27000 [ 72.154893] [ffff0000c2bb708c] pgd=0000000000000000, p4d=180000023ffff403, pud=180000023f84b403, pmd=180000023f835403, +pte=0068000102bb7707 [ 72.163021] Internal error: Oops: 0000000096000021 [#1] SMP [...] [ 72.170041] CPU: 7 UID: 0 PID: 54 Comm: kworker/7:0 Tainted: G E 6.13.0-rc3+ #2 [ 72.170509] Tainted: [E]=UNSIGNED_MODULE [ 72.170720] Hardware name: QEMU QEMU Virtual Machine, BIOS edk2-stable202302-for-qemu 03/01/2023 [ 72.171192] Workqueue: events_power_efficient nft_rhash_gc [nf_tables] [ 72.171552] pstate: 21400005 (nzCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) [ 72.171915] pc : nft_rhash_gc+0x200/0x2d8 [nf_tables] [ 72.172166] lr : nft_rhash_gc+0x128/0x2d8 [nf_tables] [ 72.172546] sp : ffff800081f2bce0 [ 72.172724] x29: ffff800081f2bd40 x28: ffff0000c2bb708c x27: 0000000000000038 [ 72.173078] x26: ffff0000c6780ef0 x25: ffff0000c643df00 x24: ffff0000c6778f78 [ 72.173431] x23: 000000000000001a x22: ffff0000c4b1f000 x21: ffff0000c6780f78 [ 72.173782] x20: ffff0000c2bb70dc x19: ffff0000c2bb7080 x18: 0000000000000000 [ 72.174135] x17: ffff0000c0a4e1c0 x16: 0000000000003000 x15: 0000ac26d173b978 [ 72.174485] x14: ffffffffffffffff x13: 0000000000000030 x12: ffff0000c6780ef0 [ 72.174841] x11: 0000000000000000 x10: ffff800081f2bcf8 x9 : ffff0000c3000000 [ 72.175193] x8 : 00000000000004be x7 : 0000000000000000 x6 : 0000000000000000 [ 72.175544] x5 : 0000000000000040 x4 : ffff0000c3000010 x3 : 0000000000000000 [ 72.175871] x2 : 0000000000003a98 x1 : ffff0000c2bb708c x0 : 0000000000000004 [ 72.176207] Call trace: [ 72.176316] nft_rhash_gc+0x200/0x2d8 [nf_tables] (P) [ 72.176653] process_one_work+0x178/0x3d0 [ 72.176831] worker_thread+0x200/0x3f0 [ 72.176995] kthread+0xe8/0xf8 [ 72.177130] ret_from_fork+0x10/0x20 [ 72.177289] Code: 54fff984 d503201f d2800080 91003261 (f820303f) [ 72.177557] ---[ end trace 0000000000000000 ]--- Align struct nft_set_ext to word size to address this and documentation it. pahole reports that this increases the size of elements for rhash and pipapo in 8 bytes on x86_64. Fixes: 7ffc748 ("netfilter: nft_set_hash: skip duplicated elements pending gc run") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Using mutex lock in IO hot path causes the kernel BUG sleeping while atomic. Shinichiro[1], first encountered this issue while running blktest nvme/052 shown below: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:585 in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 996, name: (udev-worker) preempt_count: 0, expected: 0 RCU nest depth: 1, expected: 0 2 locks held by (udev-worker)/996: #0: ffff8881004570c8 (mapping.invalidate_lock){.+.+}-{3:3}, at: page_cache_ra_unbounded+0x155/0x5c0 #1: ffffffff8607eaa0 (rcu_read_lock){....}-{1:2}, at: blk_mq_flush_plug_list+0xa75/0x1950 CPU: 2 UID: 0 PID: 996 Comm: (udev-worker) Not tainted 6.12.0-rc3+ #339 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x6a/0x90 __might_resched.cold+0x1f7/0x23d ? __pfx___might_resched+0x10/0x10 ? vsnprintf+0xdeb/0x18f0 __mutex_lock+0xf4/0x1220 ? nvmet_subsys_nsid_exists+0xb9/0x150 [nvmet] ? __pfx_vsnprintf+0x10/0x10 ? __pfx___mutex_lock+0x10/0x10 ? snprintf+0xa5/0xe0 ? xas_load+0x1ce/0x3f0 ? nvmet_subsys_nsid_exists+0xb9/0x150 [nvmet] nvmet_subsys_nsid_exists+0xb9/0x150 [nvmet] ? __pfx_nvmet_subsys_nsid_exists+0x10/0x10 [nvmet] nvmet_req_find_ns+0x24e/0x300 [nvmet] nvmet_req_init+0x694/0xd40 [nvmet] ? blk_mq_start_request+0x11c/0x750 ? nvme_setup_cmd+0x369/0x990 [nvme_core] nvme_loop_queue_rq+0x2a7/0x7a0 [nvme_loop] ? __pfx___lock_acquire+0x10/0x10 ? __pfx_nvme_loop_queue_rq+0x10/0x10 [nvme_loop] __blk_mq_issue_directly+0xe2/0x1d0 ? __pfx___blk_mq_issue_directly+0x10/0x10 ? blk_mq_request_issue_directly+0xc2/0x140 blk_mq_plug_issue_direct+0x13f/0x630 ? lock_acquire+0x2d/0xc0 ? blk_mq_flush_plug_list+0xa75/0x1950 blk_mq_flush_plug_list+0xa9d/0x1950 ? __pfx_blk_mq_flush_plug_list+0x10/0x10 ? __pfx_mpage_readahead+0x10/0x10 __blk_flush_plug+0x278/0x4d0 ? __pfx___blk_flush_plug+0x10/0x10 ? lock_release+0x460/0x7a0 blk_finish_plug+0x4e/0x90 read_pages+0x51b/0xbc0 ? __pfx_read_pages+0x10/0x10 ? lock_release+0x460/0x7a0 page_cache_ra_unbounded+0x326/0x5c0 force_page_cache_ra+0x1ea/0x2f0 filemap_get_pages+0x59e/0x17b0 ? __pfx_filemap_get_pages+0x10/0x10 ? lock_is_held_type+0xd5/0x130 ? __pfx___might_resched+0x10/0x10 ? find_held_lock+0x2d/0x110 filemap_read+0x317/0xb70 ? up_write+0x1ba/0x510 ? __pfx_filemap_read+0x10/0x10 ? inode_security+0x54/0xf0 ? selinux_file_permission+0x36d/0x420 blkdev_read_iter+0x143/0x3b0 vfs_read+0x6ac/0xa20 ? __pfx_vfs_read+0x10/0x10 ? __pfx_vm_mmap_pgoff+0x10/0x10 ? __pfx___seccomp_filter+0x10/0x10 ksys_read+0xf7/0x1d0 ? __pfx_ksys_read+0x10/0x10 do_syscall_64+0x93/0x180 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on_prepare+0x16d/0x400 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f565bd1ce11 Code: 00 48 8b 15 09 90 0d 00 f7 d8 64 89 02 b8 ff ff ff ff eb bd e8 d0 ad 01 00 f3 0f 1e fa 80 3d 35 12 0e 00 00 74 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 4f c3 66 0f 1f 44 00 00 55 48 89 e5 48 83 ec RSP: 002b:00007ffd6e7a20c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000001000 RCX: 00007f565bd1ce11 RDX: 0000000000001000 RSI: 00007f565babb000 RDI: 0000000000000014 RBP: 00007ffd6e7a2130 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000556000bfa610 R11: 0000000000000246 R12: 000000003ffff000 R13: 0000556000bfa5b0 R14: 0000000000000e00 R15: 0000556000c07328 </TASK> Apparently, the above issue is caused due to using mutex lock while we're in IO hot path. It's a regression caused with commit 5053639 ("nvmet: fix nvme status code when namespace is disabled"). The mutex ->su_mutex is used to find whether a disabled nsid exists in the config group or not. This is to differentiate between a nsid that is disabled vs non-existent. To mitigate the above issue, we've worked upon a fix[2] where we now insert nsid in subsys Xarray as soon as it's created under config group and later when that nsid is enabled, we add an Xarray mark on it and set ns->enabled to true. The Xarray mark is useful while we need to loop through all enabled namepsaces under a subsystem using xa_for_each_marked() API. If later a nsid is disabled then we clear Xarray mark from it and also set ns->enabled to false. It's only when nsid is deleted from the config group we delete it from the Xarray. So with this change, now we could easily differentiate a nsid is disabled (i.e. Xarray entry for ns exists but ns->enabled is set to false) vs non- existent (i.e.Xarray entry for ns doesn't exist). Link: https://lore.kernel.org/linux-nvme/20241022070252.GA11389@lst.de/ [2] Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com> Closes: https://lore.kernel.org/linux-nvme/tqcy3sveity7p56v7ywp7ssyviwcb3w4623cnxj3knoobfcanq@yxgt2mjkbkam/ [1] Fixes: 5053639 ("nvmet: fix nvme status code when namespace is disabled") Fix-suggested-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Nilay Shroff <nilay@linux.ibm.com> Signed-off-by: Keith Busch <kbusch@kernel.org>

Initialize meter_urb array before use in mixer_us16x08.c. CID 1410197: (#1 of 1): Uninitialized scalar variable (UNINIT) uninit_use_in_call: Using uninitialized value *meter_urb when calling get_meter_levels_from_urb. Coverity Link: https://scan7.scan.coverity.com/#/project-view/52849/11354?selectedIssue=1410197 Fixes: d2bb390 ("ALSA: usb-audio: Tascam US-16x08 DSP mixer quirk") Signed-off-by: Tanya Agarwal <tanyaagarwal25699@gmail.com> Link: https://patch.msgid.link/20241229060240.1642-1-tanyaagarwal25699@gmail.com Signed-off-by: Takashi Iwai <tiwai@suse.de>

This reverts commit fd620fc. Boot failures reported by KernelCI: [ 4.395400] mediatek-drm mediatek-drm.5.auto: bound 1c014000.merge (ops 0xffffd35fd12975f8) [ 4.396155] mediatek-drm mediatek-drm.5.auto: bound 1c000000.ovl (ops 0xffffd35fd12977b8) [ 4.411951] mediatek-drm mediatek-drm.5.auto: bound 1c002000.rdma (ops 0xffffd35fd12989c0) [ 4.536837] mediatek-drm mediatek-drm.5.auto: bound 1c004000.ccorr (ops 0xffffd35fd1296cf0) [ 4.545181] mediatek-drm mediatek-drm.5.auto: bound 1c005000.aal (ops 0xffffd35fd1296a80) [ 4.553344] mediatek-drm mediatek-drm.5.auto: bound 1c006000.gamma (ops 0xffffd35fd12972b0) [ 4.561680] mediatek-drm mediatek-drm.5.auto: bound 1c014000.merge (ops 0xffffd35fd12975f8) [ 4.570025] ------------[ cut here ]------------ [ 4.574630] refcount_t: underflow; use-after-free. [ 4.579416] WARNING: CPU: 6 PID: 81 at lib/refcount.c:28 refcount_warn_saturate+0xf4/0x148 [ 4.587670] Modules linked in: [ 4.590714] CPU: 6 UID: 0 PID: 81 Comm: kworker/u32:3 Tainted: G W 6.12.0 #1 cab58e2e59020ebd4be8ada89a65f465a316c742 [ 4.602695] Tainted: [W]=WARN [ 4.605649] Hardware name: Acer Tomato (rev2) board (DT) [ 4.610947] Workqueue: events_unbound deferred_probe_work_func [ 4.616768] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 4.623715] pc : refcount_warn_saturate+0xf4/0x148 [ 4.628493] lr : refcount_warn_saturate+0xf4/0x148 [ 4.633270] sp : ffff8000807639c0 [ 4.636571] x29: ffff8000807639c0 x28: ffff34ff4116c640 x27: ffff34ff4368e080 [ 4.643693] x26: ffffd35fd1299ac8 x25: ffff34ff46c8c410 x24: 0000000000000000 [ 4.650814] x23: ffff34ff4368e080 x22: 00000000fffffdfb x21: 0000000000000002 [ 4.657934] x20: ffff34ff470c6000 x19: ffff34ff410c7c10 x18: 0000000000000006 [ 4.665055] x17: 666678302073706f x16: 2820656772656d2e x15: ffff800080763440 [ 4.672176] x14: 0000000000000000 x13: 2e656572662d7265 x12: ffffd35fd2ed14f0 [ 4.679297] x11: 0000000000000001 x10: 0000000000000001 x9 : ffffd35fd0342150 [ 4.686418] x8 : c0000000ffffdfff x7 : ffffd35fd2e21450 x6 : 00000000000affa8 [ 4.693539] x5 : ffffd35fd2ed1498 x4 : 0000000000000000 x3 : 0000000000000000 [ 4.700660] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff34ff40932580 [ 4.707781] Call trace: [ 4.710216] refcount_warn_saturate+0xf4/0x148 (P) [ 4.714993] refcount_warn_saturate+0xf4/0x148 (L) [ 4.719772] kobject_put+0x110/0x118 [ 4.723335] put_device+0x1c/0x38 [ 4.726638] mtk_drm_bind+0x294/0x5c0 [ 4.730289] try_to_bring_up_aggregate_device+0x16c/0x1e0 [ 4.735673] __component_add+0xbc/0x1c0 [ 4.739495] component_add+0x1c/0x30 [ 4.743058] mtk_disp_rdma_probe+0x140/0x210 [ 4.747314] platform_probe+0x70/0xd0 [ 4.750964] really_probe+0xc4/0x2a8 [ 4.754527] __driver_probe_device+0x80/0x140 [ 4.758870] driver_probe_device+0x44/0x120 [ 4.763040] __device_attach_driver+0xc0/0x108 [ 4.767470] bus_for_each_drv+0x8c/0xf0 [ 4.771294] __device_attach+0xa4/0x198 [ 4.775117] device_initial_probe+0x1c/0x30 [ 4.779286] bus_probe_device+0xb4/0xc0 [ 4.783109] deferred_probe_work_func+0xb0/0x100 [ 4.787714] process_one_work+0x18c/0x420 [ 4.791712] worker_thread+0x30c/0x418 [ 4.795449] kthread+0x128/0x138 [ 4.798665] ret_from_fork+0x10/0x20 [ 4.802229] ---[ end trace 0000000000000000 ]--- Fixes: fd620fc ("drm/mediatek: Switch to for_each_child_of_node_scoped()") Cc: stable@vger.kernel.org Cc: Javier Carrasco <javier.carrasco.cruz@gmail.com> Reported-by: Sasha Levin <sashal@kernel.org> Closes: https://lore.kernel.org/lkml/Z0lNHdwQ3rODHQ2c@sashalap/T/#mfaa6343cfd4d59aae5912b095c0693c0553e746c Link: https://patchwork.kernel.org/project/dri-devel/patch/20241223151218.7958-1-chunkuang.hu@kernel.org/ Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

syzbot reports that a recent fix causes nesting issues between the (now) raw timeoutlock and the eventfd locking: ============================= [ BUG: Invalid wait context ] 6.13.0-rc4-00080-g9828a4c0901f #29 Not tainted ----------------------------- kworker/u32:0/68094 is trying to lock: ffff000014d7a520 (&ctx->wqh#2){..-.}-{3:3}, at: eventfd_signal_mask+0x64/0x180 other info that might help us debug this: context-{5:5} 6 locks held by kworker/u32:0/68094: #0: ffff0000c1d98148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x4e8/0xfc0 #1: ffff80008d927c78 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x53c/0xfc0 #2: ffff0000c59bc3d8 (&ctx->completion_lock){+.+.}-{3:3}, at: io_kill_timeouts+0x40/0x180 #3: ffff0000c59bc358 (&ctx->timeout_lock){-.-.}-{2:2}, at: io_kill_timeouts+0x48/0x180 #4: ffff800085127aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x8/0x38 #5: ffff800085127aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x8/0x38 stack backtrace: CPU: 7 UID: 0 PID: 68094 Comm: kworker/u32:0 Not tainted 6.13.0-rc4-00080-g9828a4c0901f #29 Hardware name: linux,dummy-virt (DT) Workqueue: iou_exit io_ring_exit_work Call trace: show_stack+0x1c/0x30 (C) __dump_stack+0x24/0x30 dump_stack_lvl+0x60/0x80 dump_stack+0x14/0x20 __lock_acquire+0x19f8/0x60c8 lock_acquire+0x1a4/0x540 _raw_spin_lock_irqsave+0x90/0xd0 eventfd_signal_mask+0x64/0x180 io_eventfd_signal+0x64/0x108 io_req_local_work_add+0x294/0x430 __io_req_task_work_add+0x1c0/0x270 io_kill_timeout+0x1f0/0x288 io_kill_timeouts+0xd4/0x180 io_uring_try_cancel_requests+0x2e8/0x388 io_ring_exit_work+0x150/0x550 process_one_work+0x5e8/0xfc0 worker_thread+0x7ec/0xc80 kthread+0x24c/0x300 ret_from_fork+0x10/0x20 because after the preempt-rt fix for the timeout lock nesting inside the io-wq lock, we now have the eventfd spinlock nesting inside the raw timeout spinlock. Rather than play whack-a-mole with other nesting on the timeout lock, split the deletion and killing of timeouts so queueing the task_work for the timeout cancelations can get done outside of the timeout lock. Reported-by: syzbot+b1fc199a40b65d601b65@syzkaller.appspotmail.com Fixes: 020b40f ("io_uring: make ctx->timeout_lock a raw spinlock") Signed-off-by: Jens Axboe <axboe@kernel.dk>

Syzbot reported the following splat: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 UID: 0 PID: 5836 Comm: sshd Not tainted 6.13.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024 RIP: 0010:_compound_head include/linux/page-flags.h:242 [inline] RIP: 0010:put_page+0x23/0x260 include/linux/mm.h:1552 Code: 90 90 90 90 90 90 90 55 41 57 41 56 53 49 89 fe 48 bd 00 00 00 00 00 fc ff df e8 f8 5e 12 f8 49 8d 5e 08 48 89 d8 48 c1 e8 03 <80> 3c 28 00 74 08 48 89 df e8 8f c7 78 f8 48 8b 1b 48 89 de 48 83 RSP: 0000:ffffc90003916c90 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 0000000000000008 RCX: ffff888030458000 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff898ca81d R09: 1ffff110054414ac R10: dffffc0000000000 R11: ffffed10054414ad R12: 0000000000000007 R13: ffff88802a20a542 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f34f496e800(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9d6ec9ec28 CR3: 000000004d260000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> skb_page_unref include/linux/skbuff_ref.h:43 [inline] __skb_frag_unref include/linux/skbuff_ref.h:56 [inline] skb_release_data+0x483/0x8a0 net/core/skbuff.c:1119 skb_release_all net/core/skbuff.c:1190 [inline] __kfree_skb+0x55/0x70 net/core/skbuff.c:1204 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3436 [inline] tcp_ack+0x2442/0x6bc0 net/ipv4/tcp_input.c:4032 tcp_rcv_state_process+0x8eb/0x44e0 net/ipv4/tcp_input.c:6805 tcp_v4_do_rcv+0x77d/0xc70 net/ipv4/tcp_ipv4.c:1939 tcp_v4_rcv+0x2dc0/0x37f0 net/ipv4/tcp_ipv4.c:2351 ip_protocol_deliver_rcu+0x22e/0x440 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x341/0x5f0 net/ipv4/ip_input.c:233 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5672 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5785 process_backlog+0x662/0x15b0 net/core/dev.c:6117 __napi_poll+0xcb/0x490 net/core/dev.c:6883 napi_poll net/core/dev.c:6952 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7074 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x57/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0033:0x7f34f4519ad5 Code: 85 d2 74 0d 0f 10 02 48 8d 54 24 20 0f 11 44 24 20 64 8b 04 25 18 00 00 00 85 c0 75 27 41 b8 08 00 00 00 b8 0f 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 75 48 8b 15 24 73 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffec5b32ce0 EFLAGS: 00000246 RAX: 0000000000000001 RBX: 00000000000668a0 RCX: 00007f34f4519ad5 RDX: 00007ffec5b32d00 RSI: 0000000000000004 RDI: 0000564f4bc6cae0 RBP: 0000564f4bc6b5a0 R08: 0000000000000008 R09: 0000000000000000 R10: 00007ffec5b32de8 R11: 0000000000000246 R12: 0000564f48ea8aa4 R13: 0000000000000001 R14: 0000564f48ea93e8 R15: 00007ffec5b32d68 </TASK> Eric noted a probable shinfo->nr_frags corruption, which indeed occurs. The root cause is a buggy MPTCP option len computation in some circumstances: the ADD_ADDR option should be mutually exclusive with DSS since the blamed commit. Still, mptcp_established_options_add_addr() tries to set the relevant info in mptcp_out_options, if the remaining space is large enough even when DSS is present. Since the ADD_ADDR infos and the DSS share the same union fields, adding first corrupts the latter. In the worst-case scenario, such corruption increases the DSS binary layout, exceeding the computed length and possibly overwriting the skb shared info. Address the issue by enforcing mutual exclusion in mptcp_established_options_add_addr(), too. Cc: stable@vger.kernel.org Reported-by: syzbot+38a095a81f30d82884c1@syzkaller.appspotmail.com Closes: multipath-tcp/mptcp_net-next#538 Fixes: 1bff1e4 ("mptcp: optimize out option generation") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/025d9df8cde3c9a557befc47e9bc08fbbe3476e5.1734771049.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

…le_direct_reclaim() The task sometimes continues looping in throttle_direct_reclaim() because allow_direct_reclaim(pgdat) keeps returning false. #0 [ffff80002cb6f8d0] __switch_to at ffff8000080095ac #1 [ffff80002cb6f900] __schedule at ffff800008abbd1c #2 [ffff80002cb6f990] schedule at ffff800008abc50c #3 [ffff80002cb6f9b0] throttle_direct_reclaim at ffff800008273550 #4 [ffff80002cb6fa20] try_to_free_pages at ffff800008277b68 #5 [ffff80002cb6fae0] __alloc_pages_nodemask at ffff8000082c4660 #6 [ffff80002cb6fc50] alloc_pages_vma at ffff8000082e4a98 #7 [ffff80002cb6fca0] do_anonymous_page at ffff80000829f5a8 #8 [ffff80002cb6fce0] __handle_mm_fault at ffff8000082a5974 #9 [ffff80002cb6fd90] handle_mm_fault at ffff8000082a5bd4 At this point, the pgdat contains the following two zones: NODE: 4 ZONE: 0 ADDR: ffff00817fffe540 NAME: "DMA32" SIZE: 20480 MIN/LOW/HIGH: 11/28/45 VM_STAT: NR_FREE_PAGES: 359 NR_ZONE_INACTIVE_ANON: 18813 NR_ZONE_ACTIVE_ANON: 0 NR_ZONE_INACTIVE_FILE: 50 NR_ZONE_ACTIVE_FILE: 0 NR_ZONE_UNEVICTABLE: 0 NR_ZONE_WRITE_PENDING: 0 NR_MLOCK: 0 NR_BOUNCE: 0 NR_ZSPAGES: 0 NR_FREE_CMA_PAGES: 0 NODE: 4 ZONE: 1 ADDR: ffff00817fffec00 NAME: "Normal" SIZE: 8454144 PRESENT: 98304 MIN/LOW/HIGH: 68/166/264 VM_STAT: NR_FREE_PAGES: 146 NR_ZONE_INACTIVE_ANON: 94668 NR_ZONE_ACTIVE_ANON: 3 NR_ZONE_INACTIVE_FILE: 735 NR_ZONE_ACTIVE_FILE: 78 NR_ZONE_UNEVICTABLE: 0 NR_ZONE_WRITE_PENDING: 0 NR_MLOCK: 0 NR_BOUNCE: 0 NR_ZSPAGES: 0 NR_FREE_CMA_PAGES: 0 In allow_direct_reclaim(), while processing ZONE_DMA32, the sum of inactive/active file-backed pages calculated in zone_reclaimable_pages() based on the result of zone_page_state_snapshot() is zero. Additionally, since this system lacks swap, the calculation of inactive/ active anonymous pages is skipped. crash> p nr_swap_pages nr_swap_pages = $1937 = { counter = 0 } As a result, ZONE_DMA32 is deemed unreclaimable and skipped, moving on to the processing of the next zone, ZONE_NORMAL, despite ZONE_DMA32 having free pages significantly exceeding the high watermark. The problem is that the pgdat->kswapd_failures hasn't been incremented. crash> px ((struct pglist_data *) 0xffff00817fffe540)->kswapd_failures $1935 = 0x0 This is because the node deemed balanced. The node balancing logic in balance_pgdat() evaluates all zones collectively. If one or more zones (e.g., ZONE_DMA32) have enough free pages to meet their watermarks, the entire node is deemed balanced. This causes balance_pgdat() to exit early before incrementing the kswapd_failures, as it considers the overall memory state acceptable, even though some zones (like ZONE_NORMAL) remain under significant pressure. The patch ensures that zone_reclaimable_pages() includes free pages (NR_FREE_PAGES) in its calculation when no other reclaimable pages are available (e.g., file-backed or anonymous pages). This change prevents zones like ZONE_DMA32, which have sufficient free pages, from being mistakenly deemed unreclaimable. By doing so, the patch ensures proper node balancing, avoids masking pressure on other zones like ZONE_NORMAL, and prevents infinite loops in throttle_direct_reclaim() caused by allow_direct_reclaim(pgdat) repeatedly returning false. The kernel hangs due to a task stuck in throttle_direct_reclaim(), caused by a node being incorrectly deemed balanced despite pressure in certain zones, such as ZONE_NORMAL. This issue arises from zone_reclaimable_pages() returning 0 for zones without reclaimable file- backed or anonymous pages, causing zones like ZONE_DMA32 with sufficient free pages to be skipped. The lack of swap or reclaimable pages results in ZONE_DMA32 being ignored during reclaim, masking pressure in other zones. Consequently, pgdat->kswapd_failures remains 0 in balance_pgdat(), preventing fallback mechanisms in allow_direct_reclaim() from being triggered, leading to an infinite loop in throttle_direct_reclaim(). This patch modifies zone_reclaimable_pages() to account for free pages (NR_FREE_PAGES) when no other reclaimable pages exist. This ensures zones with sufficient free pages are not skipped, enabling proper balancing and reclaim behavior. [akpm@linux-foundation.org: coding-style cleanups] Link: https://lkml.kernel.org/r/20241130164346.436469-1-snishika@redhat.com Link: https://lkml.kernel.org/r/20241130161236.433747-2-snishika@redhat.com Fixes: 5a1c84b ("mm: remove reclaim and compaction retry approximations") Signed-off-by: Seiji Nishikawa <snishika@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

…nt message Address a bug in the kernel that triggers a "sleeping function called from invalid context" warning when /sys/kernel/debug/kmemleak is printed under specific conditions: - CONFIG_PREEMPT_RT=y - Set SELinux as the LSM for the system - Set kptr_restrict to 1 - kmemleak buffer contains at least one item BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 136, name: cat preempt_count: 1, expected: 0 RCU nest depth: 2, expected: 2 6 locks held by cat/136: #0: ffff32e64bcbf950 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xb8/0xe30 #1: ffffafe6aaa9dea0 (scan_mutex){+.+.}-{3:3}, at: kmemleak_seq_start+0x34/0x128 #3: ffff32e6546b1cd0 (&object->lock){....}-{2:2}, at: kmemleak_seq_show+0x3c/0x1e0 #4: ffffafe6aa8d8560 (rcu_read_lock){....}-{1:2}, at: has_ns_capability_noaudit+0x8/0x1b0 #5: ffffafe6aabbc0f8 (notif_lock){+.+.}-{2:2}, at: avc_compute_av+0xc4/0x3d0 irq event stamp: 136660 hardirqs last enabled at (136659): [<ffffafe6a80fd7a0>] _raw_spin_unlock_irqrestore+0xa8/0xd8 hardirqs last disabled at (136660): [<ffffafe6a80fd85c>] _raw_spin_lock_irqsave+0x8c/0xb0 softirqs last enabled at (0): [<ffffafe6a5d50b28>] copy_process+0x11d8/0x3df8 softirqs last disabled at (0): [<0000000000000000>] 0x0 Preemption disabled at: [<ffffafe6a6598a4c>] kmemleak_seq_show+0x3c/0x1e0 CPU: 1 UID: 0 PID: 136 Comm: cat Tainted: G E 6.11.0-rt7+ #34 Tainted: [E]=UNSIGNED_MODULE Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0xa0/0x128 show_stack+0x1c/0x30 dump_stack_lvl+0xe8/0x198 dump_stack+0x18/0x20 rt_spin_lock+0x8c/0x1a8 avc_perm_nonode+0xa0/0x150 cred_has_capability.isra.0+0x118/0x218 selinux_capable+0x50/0x80 security_capable+0x7c/0xd0 has_ns_capability_noaudit+0x94/0x1b0 has_capability_noaudit+0x20/0x30 restricted_pointer+0x21c/0x4b0 pointer+0x298/0x760 vsnprintf+0x330/0xf70 seq_printf+0x178/0x218 print_unreferenced+0x1a4/0x2d0 kmemleak_seq_show+0xd0/0x1e0 seq_read_iter+0x354/0xe30 seq_read+0x250/0x378 full_proxy_read+0xd8/0x148 vfs_read+0x190/0x918 ksys_read+0xf0/0x1e0 __arm64_sys_read+0x70/0xa8 invoke_syscall.constprop.0+0xd4/0x1d8 el0_svc+0x50/0x158 el0t_64_sync+0x17c/0x180 %pS and %pK, in the same back trace line, are redundant, and %pS can void %pK service in certain contexts. %pS alone already provides the necessary information, and if it cannot resolve the symbol, it falls back to printing the raw address voiding the original intent behind the %pK. Additionally, %pK requires a privilege check CAP_SYSLOG enforced through the LSM, which can trigger a "sleeping function called from invalid context" warning under RT_PREEMPT kernels when the check occurs in an atomic context. This issue may also affect other LSMs. This change avoids the unnecessary privilege check and resolves the sleeping function warning without any loss of information. Link: https://lkml.kernel.org/r/20241217142032.55793-1-acarmina@redhat.com Fixes: 3a6f33d ("mm/kmemleak: use %pK to display kernel pointers in backtrace") Signed-off-by: Alessandro Carminati <acarmina@redhat.com> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Clément Léger <clement.leger@bootlin.com> Cc: Alessandro Carminati <acarmina@redhat.com> Cc: Eric Chanudet <echanude@redhat.com> Cc: Gabriele Paoloni <gpaoloni@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

The intermediate variable in the PERCPU_PTR() macro results in a kernel panic on boot [1] due to a compiler bug seen when compiling the kernel (+ KASAN) with gcc 11.3.1, but not when compiling with latest gcc (v14.2)/clang(v18.1). To solve it, remove the intermediate variable (which is not needed) and keep the casting that resolves the address space checks. [1] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] CPU: 0 UID: 0 PID: 547 Comm: iptables Not tainted 6.13.0-rc1_external_tested-master #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 RIP: 0010:nf_ct_netns_do_get+0x139/0x540 Code: 03 00 00 48 81 c4 88 00 00 00 5b 5d 41 5c 41 5d 41 5e 41 5f c3 4d 8d 75 08 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e 27 03 00 00 41 8b 45 08 83 c0 RSP: 0018:ffff888116df75e8 EFLAGS: 00010207 RAX: dffffc0000000000 RBX: 1ffff11022dbeebe RCX: ffffffff839a2382 RDX: 0000000000000003 RSI: 0000000000000008 RDI: ffff88842ec46d10 RBP: 0000000000000002 R08: 0000000000000000 R09: fffffbfff0b0860c R10: ffff888116df75e8 R11: 0000000000000001 R12: ffffffff879d6a80 R13: 0000000000000016 R14: 000000000000001e R15: ffff888116df7908 FS: 00007fba01646740(0000) GS:ffff88842ec00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055bd901800d8 CR3: 00000001205f0003 CR4: 0000000000172eb0 Call Trace: <TASK> ? die_addr+0x3d/0xa0 ? exc_general_protection+0x144/0x220 ? asm_exc_general_protection+0x22/0x30 ? __mutex_lock+0x2c2/0x1d70 ? nf_ct_netns_do_get+0x139/0x540 ? nf_ct_netns_do_get+0xb5/0x540 ? net_generic+0x1f0/0x1f0 ? __create_object+0x5e/0x80 xt_check_target+0x1f0/0x930 ? textify_hooks.constprop.0+0x110/0x110 ? pcpu_alloc_noprof+0x7cd/0xcf0 ? xt_find_target+0x148/0x1e0 find_check_entry.constprop.0+0x6c0/0x920 ? get_info+0x380/0x380 ? __virt_addr_valid+0x1df/0x3b0 ? kasan_quarantine_put+0xe3/0x200 ? kfree+0x13e/0x3d0 ? translate_table+0xaf5/0x1750 translate_table+0xbd8/0x1750 ? ipt_unregister_table_exit+0x30/0x30 ? __might_fault+0xbb/0x170 do_ipt_set_ctl+0x408/0x1340 ? nf_sockopt_find.constprop.0+0x17b/0x1f0 ? lock_downgrade+0x680/0x680 ? lockdep_hardirqs_on_prepare+0x284/0x400 ? ipt_register_table+0x440/0x440 ? bit_wait_timeout+0x160/0x160 nf_setsockopt+0x6f/0xd0 raw_setsockopt+0x7e/0x200 ? raw_bind+0x590/0x590 ? do_user_addr_fault+0x812/0xd20 do_sock_setsockopt+0x1e2/0x3f0 ? move_addr_to_user+0x90/0x90 ? lock_downgrade+0x680/0x680 __sys_setsockopt+0x9e/0x100 __x64_sys_setsockopt+0xb9/0x150 ? do_syscall_64+0x33/0x140 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7fba015134ce Code: 0f 1f 40 00 48 8b 15 59 69 0e 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b1 0f 1f 00 f3 0f 1e fa 49 89 ca b8 36 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 0a c3 66 0f 1f 84 00 00 00 00 00 48 8b 15 21 RSP: 002b:00007ffd9de6f388 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 000055bd9017f490 RCX: 00007fba015134ce RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 0000000000000500 R08: 0000000000000560 R09: 0000000000000052 R10: 000055bd901800e0 R11: 0000000000000246 R12: 000055bd90180140 R13: 000055bd901800e0 R14: 000055bd9017f498 R15: 000055bd9017ff10 </TASK> Modules linked in: xt_MASQUERADE nf_conntrack_netlink nfnetlink xt_addrtype iptable_nat nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcgss oid_registry overlay zram zsmalloc mlx4_ib mlx4_en mlx4_core rpcrdma rdma_ucm ib_uverbs ib_iser libiscsi scsi_transport_iscsi fuse ib_umad rdma_cm ib_ipoib iw_cm ib_cm ib_core ---[ end trace 0000000000000000 ]--- [akpm@linux-foundation.org: simplification, per Uros] Link: https://lkml.kernel.org/r/20241219121828.2120780-1-gal@nvidia.com Fixes: dabddd6 ("percpu: cast percpu pointer in PERCPU_PTR() via unsigned long") Signed-off-by: Gal Pressman <gal@nvidia.com> Closes: https://lore.kernel.org/all/7590f546-4021-4602-9252-0d525de35b52@nvidia.com Cc: Uros Bizjak <ubizjak@gmail.com> Cc: Bill Wendling <morbo@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Justin Stitt <justinstitt@google.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

When driver processes the internal state change command, it use an asynchronous thread to process the command operation. If the main thread detects that the task has timed out, the asynchronous thread will panic when executing the completion notification because the main thread completion object has been released. BUG: unable to handle page fault for address: fffffffffffffff8 PGD 1f283a067 P4D 1f283a067 PUD 1f283c067 PMD 0 Oops: 0000 [#1] PREEMPT SMP NOPTI RIP: 0010:complete_all+0x3e/0xa0 [...] Call Trace: <TASK> ? __die_body+0x68/0xb0 ? page_fault_oops+0x379/0x3e0 ? exc_page_fault+0x69/0xa0 ? asm_exc_page_fault+0x22/0x30 ? complete_all+0x3e/0xa0 fsm_main_thread+0xa3/0x9c0 [mtk_t7xx (HASH:1400 5)] ? __pfx_autoremove_wake_function+0x10/0x10 kthread+0xd8/0x110 ? __pfx_fsm_main_thread+0x10/0x10 [mtk_t7xx (HASH:1400 5)] ? __pfx_kthread+0x10/0x10 ret_from_fork+0x38/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1b/0x30 </TASK> [...] CR2: fffffffffffffff8 ---[ end trace 0000000000000000 ]--- Use the reference counter to ensure safe release as Sergey suggests: https://lore.kernel.org/all/da90f64c-260a-4329-87bf-1f9ff20a5951@gmail.com/ Fixes: 13e920d ("net: wwan: t7xx: Add core components") Signed-off-by: Jinjian Song <jinjian.song@fibocom.com> Acked-by: Sergey Ryazanov <ryazanov.s.a@gmail.com> Link: https://patch.msgid.link/20241224041552.8711-1-jinjian.song@fibocom.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Blamed commit forgot MSG_PEEK case, allowing a crash [1] as found by syzbot. Rework vlan_get_tci() to not touch skb at all, so that it can be used from many cpus on the same skb. Add a const qualifier to skb argument. [1] skbuff: skb_under_panic: text:ffffffff8a8da482 len:32 put:14 head:ffff88807a1d5800 data:ffff88807a1d5810 tail:0x14 end:0x140 dev:<NULL> ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:206 ! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 0 UID: 0 PID: 5880 Comm: syz-executor172 Not tainted 6.13.0-rc3-syzkaller-00762-g9268abe611b0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:skb_panic net/core/skbuff.c:206 [inline] RIP: 0010:skb_under_panic+0x14b/0x150 net/core/skbuff.c:216 Code: 0b 8d 48 c7 c6 9e 6c 26 8e 48 8b 54 24 08 8b 0c 24 44 8b 44 24 04 4d 89 e9 50 41 54 41 57 41 56 e8 3a 5a 79 f7 48 83 c4 20 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 RSP: 0018:ffffc90003baf5b8 EFLAGS: 00010286 RAX: 0000000000000087 RBX: dffffc0000000000 RCX: 8565c1eec37aa000 RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 RBP: ffff88802616fb50 R08: ffffffff817f0a4c R09: 1ffff92000775e50 R10: dffffc0000000000 R11: fffff52000775e51 R12: 0000000000000140 R13: ffff88807a1d5800 R14: ffff88807a1d5810 R15: 0000000000000014 FS: 00007fa03261f6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd65753000 CR3: 0000000031720000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> skb_push+0xe5/0x100 net/core/skbuff.c:2636 vlan_get_tci+0x272/0x550 net/packet/af_packet.c:565 packet_recvmsg+0x13c9/0x1ef0 net/packet/af_packet.c:3616 sock_recvmsg_nosec net/socket.c:1044 [inline] sock_recvmsg+0x22f/0x280 net/socket.c:1066 ____sys_recvmsg+0x1c6/0x480 net/socket.c:2814 ___sys_recvmsg net/socket.c:2856 [inline] do_recvmmsg+0x426/0xab0 net/socket.c:2951 __sys_recvmmsg net/socket.c:3025 [inline] __do_sys_recvmmsg net/socket.c:3048 [inline] __se_sys_recvmmsg net/socket.c:3041 [inline] __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3041 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 Fixes: 79eecf6 ("af_packet: Handle outgoing VLAN packets without hardware offloading") Reported-by: syzbot+8400677f3fd43f37d3bc@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6772c485.050a0220.2f3838.04c6.GAE@google.com/T/#u Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Chengen Du <chengen.du@canonical.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20241230161004.2681892-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Blamed commit forgot MSG_PEEK case, allowing a crash [1] as found by syzbot. Rework vlan_get_protocol_dgram() to not touch skb at all, so that it can be used from many cpus on the same skb. Add a const qualifier to skb argument. [1] skbuff: skb_under_panic: text:ffffffff8a8ccd05 len:29 put:14 head:ffff88807fc8e400 data:ffff88807fc8e3f4 tail:0x11 end:0x140 dev:<NULL> ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:206 ! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 1 UID: 0 PID: 5892 Comm: syz-executor883 Not tainted 6.13.0-rc4-syzkaller-00054-gd6ef8b40d075 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:skb_panic net/core/skbuff.c:206 [inline] RIP: 0010:skb_under_panic+0x14b/0x150 net/core/skbuff.c:216 Code: 0b 8d 48 c7 c6 86 d5 25 8e 48 8b 54 24 08 8b 0c 24 44 8b 44 24 04 4d 89 e9 50 41 54 41 57 41 56 e8 5a 69 79 f7 48 83 c4 20 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 RSP: 0018:ffffc900038d7638 EFLAGS: 00010282 RAX: 0000000000000087 RBX: dffffc0000000000 RCX: 609ffd18ea660600 RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000 RBP: ffff88802483c8d0 R08: ffffffff817f0a8c R09: 1ffff9200071ae60 R10: dffffc0000000000 R11: fffff5200071ae61 R12: 0000000000000140 R13: ffff88807fc8e400 R14: ffff88807fc8e3f4 R15: 0000000000000011 FS: 00007fbac5e006c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbac5e00d58 CR3: 000000001238e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> skb_push+0xe5/0x100 net/core/skbuff.c:2636 vlan_get_protocol_dgram+0x165/0x290 net/packet/af_packet.c:585 packet_recvmsg+0x948/0x1ef0 net/packet/af_packet.c:3552 sock_recvmsg_nosec net/socket.c:1033 [inline] sock_recvmsg+0x22f/0x280 net/socket.c:1055 ____sys_recvmsg+0x1c6/0x480 net/socket.c:2803 ___sys_recvmsg net/socket.c:2845 [inline] do_recvmmsg+0x426/0xab0 net/socket.c:2940 __sys_recvmmsg net/socket.c:3014 [inline] __do_sys_recvmmsg net/socket.c:3037 [inline] __se_sys_recvmmsg net/socket.c:3030 [inline] __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3030 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: 79eecf6 ("af_packet: Handle outgoing VLAN packets without hardware offloading") Reported-by: syzbot+74f70bb1cb968bf09e4f@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6772c485.050a0220.2f3838.04c5.GAE@google.com/T/#u Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Chengen Du <chengen.du@canonical.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20241230161004.2681892-2-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>

[BUG] Syzbot reported a crash with the following call trace: BTRFS info (device loop0): scrub: started on devid 1 BUG: kernel NULL pointer dereference, address: 0000000000000208 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 106e70067 P4D 106e70067 PUD 107143067 PMD 0 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 UID: 0 PID: 689 Comm: repro Kdump: loaded Tainted: G O 6.13.0-rc4-custom+ #206 Tainted: [O]=OOT_MODULE Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022 RIP: 0010:find_first_extent_item+0x26/0x1f0 [btrfs] Call Trace: <TASK> scrub_find_fill_first_stripe+0x13d/0x3b0 [btrfs] scrub_simple_mirror+0x175/0x260 [btrfs] scrub_stripe+0x5d4/0x6c0 [btrfs] scrub_chunk+0xbb/0x170 [btrfs] scrub_enumerate_chunks+0x2f4/0x5f0 [btrfs] btrfs_scrub_dev+0x240/0x600 [btrfs] btrfs_ioctl+0x1dc8/0x2fa0 [btrfs] ? do_sys_openat2+0xa5/0xf0 __x64_sys_ioctl+0x97/0xc0 do_syscall_64+0x4f/0x120 entry_SYSCALL_64_after_hwframe+0x76/0x7e </TASK> [CAUSE] The reproducer is using a corrupted image where extent tree root is corrupted, thus forcing to use "rescue=all,ro" mount option to mount the image. Then it triggered a scrub, but since scrub relies on extent tree to find where the data/metadata extents are, scrub_find_fill_first_stripe() relies on an non-empty extent root. But unfortunately scrub_find_fill_first_stripe() doesn't really expect an NULL pointer for extent root, it use extent_root to grab fs_info and triggered a NULL pointer dereference. [FIX] Add an extra check for a valid extent root at the beginning of scrub_find_fill_first_stripe(). The new error path is introduced by 42437a6 ("btrfs: introduce mount option rescue=ignorebadroots"), but that's pretty old, and later commit b979547 ("btrfs: scrub: introduce helper to find and fill sector info for a scrub_stripe") changed how we do scrub. So for kernels older than 6.6, the fix will need manual backport. Reported-by: syzbot+339e9dbe3a2ca419b85d@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/67756935.050a0220.25abdd.0a12.GAE@google.com/ Fixes: 42437a6 ("btrfs: introduce mount option rescue=ignorebadroots") Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>

Since the input data length passed to zlib_compress_folios() can be arbitrary, always setting strm.avail_in to a multiple of PAGE_SIZE may cause read-in bytes to exceed the input range. Currently this triggers an assert in btrfs_compress_folios() on the debug kernel (see below). Fix strm.avail_in calculation for S390 hardware acceleration path. assertion failed: *total_in <= orig_len, in fs/btrfs/compression.c:1041 ------------[ cut here ]------------ kernel BUG at fs/btrfs/compression.c:1041! monitor event: 0040 ilc:2 [#1] PREEMPT SMP CPU: 16 UID: 0 PID: 325 Comm: kworker/u273:3 Not tainted 6.13.0-20241204.rc1.git6.fae3b21430ca.300.fc41.s390x+debug #1 Hardware name: IBM 3931 A01 703 (z/VM 7.4.0) Workqueue: btrfs-delalloc btrfs_work_helper Krnl PSW : 0704d00180000000 0000021761df6538 (btrfs_compress_folios+0x198/0x1a0) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3 Krnl GPRS: 0000000080000000 0000000000000001 0000000000000047 0000000000000000 0000000000000006 ffffff01757bb000 000001976232fcc0 000000000000130c 000001976232fcd0 000001976232fcc8 00000118ff4a0e30 0000000000000001 00000111821ab400 0000011100000000 0000021761df6534 000001976232fb58 Krnl Code: 0000021761df6528: c020006f5ef4 larl %r2,0000021762be2310 0000021761df652e: c0e5ffbd09d5 brasl %r14,00000217615978d8 #0000021761df6534: af000000 mc 0,0 >0000021761df6538: 0707 bcr 0,%r7 0000021761df653a: 0707 bcr 0,%r7 0000021761df653c: 0707 bcr 0,%r7 0000021761df653e: 0707 bcr 0,%r7 0000021761df6540: c004004bb7ec brcl 0,000002176276d518 Call Trace: [<0000021761df6538>] btrfs_compress_folios+0x198/0x1a0 ([<0000021761df6534>] btrfs_compress_folios+0x194/0x1a0) [<0000021761d97788>] compress_file_range+0x3b8/0x6d0 [<0000021761dcee7c>] btrfs_work_helper+0x10c/0x160 [<0000021761645760>] process_one_work+0x2b0/0x5d0 [<000002176164637e>] worker_thread+0x20e/0x3e0 [<000002176165221a>] kthread+0x15a/0x170 [<00000217615b859c>] __ret_from_fork+0x3c/0x60 [<00000217626e72d2>] ret_from_fork+0xa/0x38 INFO: lockdep is turned off. Last Breaking-Event-Address: [<0000021761597924>] _printk+0x4c/0x58 Kernel panic - not syncing: Fatal exception: panic_on_oops Fixes: fd1e75d ("btrfs: make compression path to be subpage compatible") CC: stable@vger.kernel.org # 6.12+ Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>

DC driver is using two different values to define the maximum number of surfaces: MAX_SURFACES and MAX_SURFACE_NUM. Consolidate MAX_SURFACES as the unique definition for surface updates across DC. It fixes page fault faced by Cosmic users on AMD display versions that support two overlay planes, since the introduction of cursor overlay mode. [Nov26 21:33] BUG: unable to handle page fault for address: 0000000051d0f08b [ +0.000015] #PF: supervisor read access in kernel mode [ +0.000006] #PF: error_code(0x0000) - not-present page [ +0.000005] PGD 0 P4D 0 [ +0.000007] Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI [ +0.000006] CPU: 4 PID: 71 Comm: kworker/u32:6 Not tainted 6.10.0+ #300 [ +0.000006] Hardware name: Valve Jupiter/Jupiter, BIOS F7A0131 01/30/2024 [ +0.000007] Workqueue: events_unbound commit_work [drm_kms_helper] [ +0.000040] RIP: 0010:copy_stream_update_to_stream.isra.0+0x30d/0x750 [amdgpu] [ +0.000847] Code: 8b 10 49 89 94 24 f8 00 00 00 48 8b 50 08 49 89 94 24 00 01 00 00 8b 40 10 41 89 84 24 08 01 00 00 49 8b 45 78 48 85 c0 74 0b <0f> b6 00 41 88 84 24 90 64 00 00 49 8b 45 60 48 85 c0 74 3b 48 8b [ +0.000010] RSP: 0018:ffffc203802f79a0 EFLAGS: 00010206 [ +0.000009] RAX: 0000000051d0f08b RBX: 0000000000000004 RCX: ffff9f964f0a8070 [ +0.000004] RDX: ffff9f9710f90e40 RSI: ffff9f96600c8000 RDI: ffff9f964f000000 [ +0.000004] RBP: ffffc203802f79f8 R08: 0000000000000000 R09: 0000000000000000 [ +0.000005] R10: 0000000000000000 R11: 0000000000000000 R12: ffff9f96600c8000 [ +0.000004] R13: ffff9f9710f90e40 R14: ffff9f964f000000 R15: ffff9f96600c8000 [ +0.000004] FS: 0000000000000000(0000) GS:ffff9f9970000000(0000) knlGS:0000000000000000 [ +0.000005] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ +0.000005] CR2: 0000000051d0f08b CR3: 00000002e6a20000 CR4: 0000000000350ef0 [ +0.000005] Call Trace: [ +0.000011] <TASK> [ +0.000010] ? __die_body.cold+0x19/0x27 [ +0.000012] ? page_fault_oops+0x15a/0x2d0 [ +0.000014] ? exc_page_fault+0x7e/0x180 [ +0.000009] ? asm_exc_page_fault+0x26/0x30 [ +0.000013] ? copy_stream_update_to_stream.isra.0+0x30d/0x750 [amdgpu] [ +0.000739] ? dc_commit_state_no_check+0xd6c/0xe70 [amdgpu] [ +0.000470] update_planes_and_stream_state+0x49b/0x4f0 [amdgpu] [ +0.000450] ? srso_return_thunk+0x5/0x5f [ +0.000009] ? commit_minimal_transition_state+0x239/0x3d0 [amdgpu] [ +0.000446] update_planes_and_stream_v2+0x24a/0x590 [amdgpu] [ +0.000464] ? srso_return_thunk+0x5/0x5f [ +0.000009] ? sort+0x31/0x50 [ +0.000007] ? amdgpu_dm_atomic_commit_tail+0x159f/0x3a30 [amdgpu] [ +0.000508] ? srso_return_thunk+0x5/0x5f [ +0.000009] ? amdgpu_crtc_get_scanout_position+0x28/0x40 [amdgpu] [ +0.000377] ? srso_return_thunk+0x5/0x5f [ +0.000009] ? drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x160/0x390 [drm] [ +0.000058] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? dma_fence_default_wait+0x8c/0x260 [ +0.000010] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? wait_for_completion_timeout+0x13b/0x170 [ +0.000006] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? dma_fence_wait_timeout+0x108/0x140 [ +0.000010] ? commit_tail+0x94/0x130 [drm_kms_helper] [ +0.000024] ? process_one_work+0x177/0x330 [ +0.000008] ? worker_thread+0x266/0x3a0 [ +0.000006] ? __pfx_worker_thread+0x10/0x10 [ +0.000004] ? kthread+0xd2/0x100 [ +0.000006] ? __pfx_kthread+0x10/0x10 [ +0.000006] ? ret_from_fork+0x34/0x50 [ +0.000004] ? __pfx_kthread+0x10/0x10 [ +0.000005] ? ret_from_fork_asm+0x1a/0x30 [ +0.000011] </TASK> Fixes: 1b04dcc ("drm/amd/display: Introduce overlay cursor mode") Suggested-by: Leo Li <sunpeng.li@amd.com> Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3693 Signed-off-by: Melissa Wen <mwen@igalia.com> Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com> Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 1c86c81a86c60f9b15d3e3f43af0363cf56063e7) Cc: stable@vger.kernel.org

dm_get_plane_scale doesn't take into account plane scaled size equal to zero, leading to a kernel oops due to division by zero. Fix by setting out-scale size as zero when the dst size is zero, similar to what is done by drm_calc_scale(). This issue started with the introduction of cursor ovelay mode that uses this function to assess cursor mode changes via dm_crtc_get_cursor_mode() before checking plane state. [Dec17 17:14] Oops: divide error: 0000 [#1] PREEMPT SMP NOPTI [ +0.000018] CPU: 5 PID: 1660 Comm: surface-DP-1 Not tainted 6.10.0+ #231 [ +0.000007] Hardware name: Valve Jupiter/Jupiter, BIOS F7A0131 01/30/2024 [ +0.000004] RIP: 0010:dm_get_plane_scale+0x3f/0x60 [amdgpu] [ +0.000553] Code: 44 0f b7 41 3a 44 0f b7 49 3e 83 e0 0f 48 0f a3 c2 73 21 69 41 28 e8 03 00 00 31 d2 41 f7 f1 31 d2 89 06 69 41 2c e8 03 00 00 <41> f7 f0 89 07 e9 d7 d8 7e e9 44 89 c8 45 89 c1 41 89 c0 eb d4 66 [ +0.000005] RSP: 0018:ffffa8df0de6b8a0 EFLAGS: 00010246 [ +0.000006] RAX: 00000000000003e8 RBX: ffff9ac65c1f6e00 RCX: ffff9ac65d055500 [ +0.000003] RDX: 0000000000000000 RSI: ffffa8df0de6b8b0 RDI: ffffa8df0de6b8b4 [ +0.000004] RBP: ffff9ac64e7a5800 R08: 0000000000000000 R09: 0000000000000a00 [ +0.000003] R10: 00000000000000ff R11: 0000000000000054 R12: ffff9ac6d0700010 [ +0.000003] R13: ffff9ac65d054f00 R14: ffff9ac65d055500 R15: ffff9ac64e7a60a0 [ +0.000004] FS: 00007f869ea00640(0000) GS:ffff9ac970080000(0000) knlGS:0000000000000000 [ +0.000004] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ +0.000003] CR2: 000055ca701becd0 CR3: 000000010e7f2000 CR4: 0000000000350ef0 [ +0.000004] Call Trace: [ +0.000007] <TASK> [ +0.000006] ? __die_body.cold+0x19/0x27 [ +0.000009] ? die+0x2e/0x50 [ +0.000007] ? do_trap+0xca/0x110 [ +0.000007] ? do_error_trap+0x6a/0x90 [ +0.000006] ? dm_get_plane_scale+0x3f/0x60 [amdgpu] [ +0.000504] ? exc_divide_error+0x38/0x50 [ +0.000005] ? dm_get_plane_scale+0x3f/0x60 [amdgpu] [ +0.000488] ? asm_exc_divide_error+0x1a/0x20 [ +0.000011] ? dm_get_plane_scale+0x3f/0x60 [amdgpu] [ +0.000593] dm_crtc_get_cursor_mode+0x33f/0x430 [amdgpu] [ +0.000562] amdgpu_dm_atomic_check+0x2ef/0x1770 [amdgpu] [ +0.000501] drm_atomic_check_only+0x5e1/0xa30 [drm] [ +0.000047] drm_mode_atomic_ioctl+0x832/0xcb0 [drm] [ +0.000050] ? __pfx_drm_mode_atomic_ioctl+0x10/0x10 [drm] [ +0.000047] drm_ioctl_kernel+0xb3/0x100 [drm] [ +0.000062] drm_ioctl+0x27a/0x4f0 [drm] [ +0.000049] ? __pfx_drm_mode_atomic_ioctl+0x10/0x10 [drm] [ +0.000055] amdgpu_drm_ioctl+0x4e/0x90 [amdgpu] [ +0.000360] __x64_sys_ioctl+0x97/0xd0 [ +0.000010] do_syscall_64+0x82/0x190 [ +0.000008] ? __pfx_drm_mode_createblob_ioctl+0x10/0x10 [drm] [ +0.000044] ? srso_return_thunk+0x5/0x5f [ +0.000006] ? drm_ioctl_kernel+0xb3/0x100 [drm] [ +0.000040] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? __check_object_size+0x50/0x220 [ +0.000007] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? drm_ioctl+0x2a4/0x4f0 [drm] [ +0.000039] ? __pfx_drm_mode_createblob_ioctl+0x10/0x10 [drm] [ +0.000043] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? __pm_runtime_suspend+0x69/0xc0 [ +0.000006] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? amdgpu_drm_ioctl+0x71/0x90 [amdgpu] [ +0.000366] ? srso_return_thunk+0x5/0x5f [ +0.000006] ? syscall_exit_to_user_mode+0x77/0x210 [ +0.000007] ? srso_return_thunk+0x5/0x5f [ +0.000005] ? do_syscall_64+0x8e/0x190 [ +0.000006] ? srso_return_thunk+0x5/0x5f [ +0.000006] ? do_syscall_64+0x8e/0x190 [ +0.000006] ? srso_return_thunk+0x5/0x5f [ +0.000007] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ +0.000008] RIP: 0033:0x55bb7cd962bc [ +0.000007] Code: 4c 89 6c 24 18 4c 89 64 24 20 4c 89 74 24 28 0f 57 c0 0f 11 44 24 30 89 c7 48 8d 54 24 08 b8 10 00 00 00 be bc 64 38 c0 0f 05 <49> 89 c7 48 83 3b 00 74 09 4c 89 c7 ff 15 62 64 99 00 48 83 7b 18 [ +0.000005] RSP: 002b:00007f869e9f4da0 EFLAGS: 00000217 ORIG_RAX: 0000000000000010 [ +0.000007] RAX: ffffffffffffffda RBX: 00007f869e9f4fb8 RCX: 000055bb7cd962bc [ +0.000004] RDX: 00007f869e9f4da8 RSI: 00000000c03864bc RDI: 000000000000003b [ +0.000003] RBP: 000055bb9ddcbcc0 R08: 00007f86541b9920 R09: 0000000000000009 [ +0.000004] R10: 0000000000000004 R11: 0000000000000217 R12: 00007f865406c6b0 [ +0.000003] R13: 00007f86541b5290 R14: 00007f865410b700 R15: 000055bb9ddcbc18 [ +0.000009] </TASK> Fixes: 1b04dcc ("drm/amd/display: Introduce overlay cursor mode") Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3729 Reported-by: Fabio Scaccabarozzi <fsvm88@gmail.com> Co-developed-by: Fabio Scaccabarozzi <fsvm88@gmail.com> Signed-off-by: Fabio Scaccabarozzi <fsvm88@gmail.com> Signed-off-by: Melissa Wen <mwen@igalia.com> Reviewed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com> Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit ab75a0d2e07942ae15d32c0a5092fd336451378c) Cc: stable@vger.kernel.org

die() can be called in exception handler, and therefore cannot sleep. However, die() takes spinlock_t which can sleep with PREEMPT_RT enabled. That causes the following warning: BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 285, name: mutex preempt_count: 110001, expected: 0 RCU nest depth: 0, expected: 0 CPU: 0 UID: 0 PID: 285 Comm: mutex Not tainted 6.12.0-rc7-00022-ge19049cf7d56-dirty #234 Hardware name: riscv-virtio,qemu (DT) Call Trace: dump_backtrace+0x1c/0x24 show_stack+0x2c/0x38 dump_stack_lvl+0x5a/0x72 dump_stack+0x14/0x1c __might_resched+0x130/0x13a rt_spin_lock+0x2a/0x5c die+0x24/0x112 do_trap_insn_illegal+0xa0/0xea _new_vmalloc_restore_context_a0+0xcc/0xd8 Oops - illegal instruction [#1] Switch to use raw_spinlock_t, which does not sleep even with PREEMPT_RT enabled. Fixes: 76d2a04 ("RISC-V: Init and Halt Code") Signed-off-by: Nam Cao <namcao@linutronix.de> Cc: stable@vger.kernel.org Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://lore.kernel.org/r/20241118091333.1185288-1-namcao@linutronix.de Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

If GuC fails to load, the driver wedges, but in the process it tries to do stuff that may not be initialized yet. This moves the xe_gt_tlb_invalidation_init() to be done earlier: as its own doc says, it's a software-only initialization and should had been named with the _early() suffix. Move it to be called by xe_gt_init_early(), so the locks and seqno are initialized, avoiding a NULL ptr deref when wedging: xe 0000:03:00.0: [drm] *ERROR* GT0: load failed: status: Reset = 0, BootROM = 0x50, UKernel = 0x00, MIA = 0x00, Auth = 0x01 xe 0000:03:00.0: [drm] *ERROR* GT0: firmware signature verification failed xe 0000:03:00.0: [drm] *ERROR* CRITICAL: Xe has declared device 0000:03:00.0 as wedged. ... BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 9 UID: 0 PID: 3908 Comm: modprobe Tainted: G U W 6.13.0-rc4-xe+ #3 Tainted: [U]=USER, [W]=WARN Hardware name: Intel Corporation Alder Lake Client Platform/AlderLake-S ADP-S DDR5 UDIMM CRB, BIOS ADLSFWI1.R00.3275.A00.2207010640 07/01/2022 RIP: 0010:xe_gt_tlb_invalidation_reset+0x75/0x110 [xe] This can be easily triggered by poking the GuC binary to force a signature failure. There will still be an extra message, xe 0000:03:00.0: [drm] *ERROR* GT0: GuC mmio request 0x4100: no reply 0x4100 but that's better than a NULL ptr deref. Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/3956 Fixes: c9474b7 ("drm/xe: Wedge the entire device") Reviewed-by: Matthew Brost <matthew.brost@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20250103001111.331684-2-lucas.demarchi@intel.com Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> (cherry picked from commit 5001ef3af8f2c972d6fd9c5221a8457556f8bea6) Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>

We found a timeout problem with the pldm command on our system. The reason is that the MCTP-I3C driver has a race condition when receiving multiple-packet messages in multi-thread, resulting in a wrong packet order problem. We identified this problem by adding a debug message to the mctp_i3c_read function. According to the MCTP spec, a multiple-packet message must be composed in sequence, and if there is a wrong sequence, the whole message will be discarded and wait for the next SOM. For example, SOM → Pkt Seq #2 → Pkt Seq #1 → Pkt Seq #3 → EOM. Therefore, we try to solve this problem by adding a mutex to the mctp_i3c_read function. Before the modification, when a command requesting a multiple-packet message response is sent consecutively, an error usually occurs within 100 loops. After the mutex, it can go through 40000 loops without any error, and it seems to run well. Fixes: c8755b2 ("mctp i3c: MCTP I3C driver") Signed-off-by: Leo Yang <Leo-Yang@quantatw.com> Link: https://patch.msgid.link/20250107031529.3296094-1-Leo-Yang@quantatw.com [pabeni@redhat.com: dropped already answered question from changelog] Signed-off-by: Paolo Abeni <pabeni@redhat.com>

When cmd_alloc_index(), fails cmd_work_handler() needs to complete ent->slotted before returning early. Otherwise the task which issued the command may hang: mlx5_core 0000:01:00.0: cmd_work_handler:877:(pid 3880418): failed to allocate command entry INFO: task kworker/13:2:4055883 blocked for more than 120 seconds. Not tainted 4.19.90-25.44.v2101.ky10.aarch64 #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/13:2 D 0 4055883 2 0x00000228 Workqueue: events mlx5e_tx_dim_work [mlx5_core] Call trace: __switch_to+0xe8/0x150 __schedule+0x2a8/0x9b8 schedule+0x2c/0x88 schedule_timeout+0x204/0x478 wait_for_common+0x154/0x250 wait_for_completion+0x28/0x38 cmd_exec+0x7a0/0xa00 [mlx5_core] mlx5_cmd_exec+0x54/0x80 [mlx5_core] mlx5_core_modify_cq+0x6c/0x80 [mlx5_core] mlx5_core_modify_cq_moderation+0xa0/0xb8 [mlx5_core] mlx5e_tx_dim_work+0x54/0x68 [mlx5_core] process_one_work+0x1b0/0x448 worker_thread+0x54/0x468 kthread+0x134/0x138 ret_from_fork+0x10/0x18 Fixes: 485d65e ("net/mlx5: Add a timeout to acquire the command queue semaphore") Signed-off-by: Chenguang Zhao <zhaochenguang@kylinos.cn> Reviewed-by: Moshe Shemesh <moshe@nvidia.com> Acked-by: Tariq Toukan <tariqt@nvidia.com> Link: https://patch.msgid.link/20250108030009.68520-1-zhaochenguang@kylinos.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Using the 'net' structure via 'current' is not recommended for different reasons. First, if the goal is to use it to read or write per-netns data, this is inconsistent with how the "generic" sysctl entries are doing: directly by only using pointers set to the table entry, e.g. table->data. Linked to that, the per-netns data should always be obtained from the table linked to the netns it had been created for, which may not coincide with the reader's or writer's netns. Another reason is that access to current->nsproxy->netns can oops if attempted when current->nsproxy had been dropped when the current task is exiting. This is what syzbot found, when using acct(2): Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] CPU: 1 UID: 0 PID: 5924 Comm: syz-executor Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:proc_scheduler+0xc6/0x3c0 net/mptcp/ctrl.c:125 Code: 03 42 80 3c 38 00 0f 85 fe 02 00 00 4d 8b a4 24 08 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 cc 02 00 00 4d 8b 7c 24 28 48 8d 84 24 c8 00 00 RSP: 0018:ffffc900034774e8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 1ffff9200068ee9e RCX: ffffc90003477620 RDX: 0000000000000005 RSI: ffffffff8b08f91e RDI: 0000000000000028 RBP: 0000000000000001 R08: ffffc90003477710 R09: 0000000000000040 R10: 0000000000000040 R11: 00000000726f7475 R12: 0000000000000000 R13: ffffc90003477620 R14: ffffc90003477710 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee3cd452d8 CR3: 000000007d116000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> proc_sys_call_handler+0x403/0x5d0 fs/proc/proc_sysctl.c:601 __kernel_write_iter+0x318/0xa80 fs/read_write.c:612 __kernel_write+0xf6/0x140 fs/read_write.c:632 do_acct_process+0xcb0/0x14a0 kernel/acct.c:539 acct_pin_kill+0x2d/0x100 kernel/acct.c:192 pin_kill+0x194/0x7c0 fs/fs_pin.c:44 mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81 cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366 task_work_run+0x14e/0x250 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xad8/0x2d70 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 get_signal+0x2576/0x2610 kernel/signal.c:3017 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fee3cb87a6a Code: Unable to access opcode bytes at 0x7fee3cb87a40. RSP: 002b:00007fffcccac688 EFLAGS: 00000202 ORIG_RAX: 0000000000000037 RAX: 0000000000000000 RBX: 00007fffcccac710 RCX: 00007fee3cb87a6a RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007fffcccac6ac R09: 00007fffcccacac7 R10: 00007fffcccac710 R11: 0000000000000202 R12: 00007fee3cd49500 R13: 00007fffcccac6ac R14: 0000000000000000 R15: 00007fee3cd4b000 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:proc_scheduler+0xc6/0x3c0 net/mptcp/ctrl.c:125 Code: 03 42 80 3c 38 00 0f 85 fe 02 00 00 4d 8b a4 24 08 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 cc 02 00 00 4d 8b 7c 24 28 48 8d 84 24 c8 00 00 RSP: 0018:ffffc900034774e8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 1ffff9200068ee9e RCX: ffffc90003477620 RDX: 0000000000000005 RSI: ffffffff8b08f91e RDI: 0000000000000028 RBP: 0000000000000001 R08: ffffc90003477710 R09: 0000000000000040 R10: 0000000000000040 R11: 00000000726f7475 R12: 0000000000000000 R13: ffffc90003477620 R14: ffffc90003477710 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee3cd452d8 CR3: 000000007d116000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) 5: 0f 85 fe 02 00 00 jne 0x309 b: 4d 8b a4 24 08 09 00 mov 0x908(%r12),%r12 12: 00 13: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1a: fc ff df 1d: 49 8d 7c 24 28 lea 0x28(%r12),%rdi 22: 48 89 fa mov %rdi,%rdx 25: 48 c1 ea 03 shr $0x3,%rdx * 29: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2d: 0f 85 cc 02 00 00 jne 0x2ff 33: 4d 8b 7c 24 28 mov 0x28(%r12),%r15 38: 48 rex.W 39: 8d .byte 0x8d 3a: 84 24 c8 test %ah,(%rax,%rcx,8) Here with 'net.mptcp.scheduler', the 'net' structure is not really needed, because the table->data already has a pointer to the current scheduler, the only thing needed from the per-netns data. Simply use 'data', instead of getting (most of the time) the same thing, but from a longer and indirect way. Fixes: 6963c50 ("mptcp: only allow set existing scheduler for net.mptcp.scheduler") Cc: stable@vger.kernel.org Reported-by: syzbot+e364f774c6f57f2c86d1@syzkaller.appspotmail.com Closes: https://lore.kernel.org/67769ecb.050a0220.3a8527.003f.GAE@google.com Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-2-5df34b2083e8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Max Makarov reported kernel panic [1] in perf user callchain code. The reason for that is the race between uprobe_free_utask and bpf profiler code doing the perf user stack unwind and is triggered within uprobe_free_utask function: - after current->utask is freed and - before current->utask is set to NULL general protection fault, probably for non-canonical address 0x9e759c37ee555c76: 0000 [#1] SMP PTI RIP: 0010:is_uprobe_at_func_entry+0x28/0x80 ... ? die_addr+0x36/0x90 ? exc_general_protection+0x217/0x420 ? asm_exc_general_protection+0x26/0x30 ? is_uprobe_at_func_entry+0x28/0x80 perf_callchain_user+0x20a/0x360 get_perf_callchain+0x147/0x1d0 bpf_get_stackid+0x60/0x90 bpf_prog_9aac297fb833e2f5_do_perf_event+0x434/0x53b ? __smp_call_single_queue+0xad/0x120 bpf_overflow_handler+0x75/0x110 ... asm_sysvec_apic_timer_interrupt+0x1a/0x20 RIP: 0010:__kmem_cache_free+0x1cb/0x350 ... ? uprobe_free_utask+0x62/0x80 ? acct_collect+0x4c/0x220 uprobe_free_utask+0x62/0x80 mm_release+0x12/0xb0 do_exit+0x26b/0xaa0 __x64_sys_exit+0x1b/0x20 do_syscall_64+0x5a/0x80 It can be easily reproduced by running following commands in separate terminals: # while :; do bpftrace -e 'uprobe:/bin/ls:_start { printf("hit\n"); }' -c ls; done # bpftrace -e 'profile:hz:100000 { @[ustack()] = count(); }' Fixing this by making sure current->utask pointer is set to NULL before we start to release the utask object. [1] grafana/pyroscope#3673 Fixes: cfa7f3d ("perf,x86: avoid missing caller address in stack traces captured in uprobe") Reported-by: Max Makarov <maxpain@linux.com> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20250109141440.2692173-1-jolsa@kernel.org

…unmounting When close a file it will be deferred to call the fput(), which will hold the inode's i_count. And when unmounting the mountpoint the evict_inodes() may skip evicting some inodes. If encrypt is enabled the kernel generate a warning when removing the encrypt keys when the skipped inodes still hold the keyring: WARNING: CPU: 4 PID: 168846 at fs/crypto/keyring.c:242 fscrypt_destroy_keyring+0x7e/0xd0 CPU: 4 PID: 168846 Comm: umount Tainted: G S 6.1.0-rc5-ceph-g72ead199864c #1 Hardware name: Supermicro SYS-5018R-WR/X10SRW-F, BIOS 2.0 12/17/2015 RIP: 0010:fscrypt_destroy_keyring+0x7e/0xd0 RSP: 0018:ffffc9000b277e28 EFLAGS: 00010202 RAX: 0000000000000002 RBX: ffff88810d52ac00 RCX: ffff88810b56aa00 RDX: 0000000080000000 RSI: ffffffff822f3a09 RDI: ffff888108f59000 RBP: ffff8881d394fb88 R08: 0000000000000028 R09: 0000000000000000 R10: 0000000000000001 R11: 11ff4fe6834fcd91 R12: ffff8881d394fc40 R13: ffff888108f59000 R14: ffff8881d394f800 R15: 0000000000000000 FS: 00007fd83f6f1080(0000) GS:ffff88885fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f918d417000 CR3: 000000017f89a005 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> generic_shutdown_super+0x47/0x120 kill_anon_super+0x14/0x30 ceph_kill_sb+0x36/0x90 [ceph] deactivate_locked_super+0x29/0x60 cleanup_mnt+0xb8/0x140 task_work_run+0x67/0xb0 exit_to_user_mode_prepare+0x23d/0x240 syscall_exit_to_user_mode+0x25/0x60 do_syscall_64+0x40/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fd83dc39e9b URL: https://tracker.ceph.com/issues/58126 Signed-off-by: Xiubo Li <xiubli@redhat.com>

6uv1s merged this pull request into testing Apr 12, 2013

6uv1s deleted the wip-3579 branch April 12, 2013 18:06

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ceph: Use pseudo-random numbers to choose mds #1

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6uv1s commented Apr 12, 2013

ceph: Use pseudo-random numbers to choose mds #1

ceph: Use pseudo-random numbers to choose mds #1

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6uv1s commented Apr 12, 2013