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INFO: rcu detected stall in aoecmd_cfg (2)

Status: upstream: reported on 2025/11/26 13:19
Reported-by: syzbot+e1fb06fe8ddf2e426517@syzkaller.appspotmail.com
First crash: 4d05h, last: 4d05h
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in aoecmd_cfg 1 2 458d 548d 0/3 auto-obsoleted due to no activity on 2024/12/07 10:13
linux-5.15 INFO: rcu detected stall in aoecmd_cfg 1 1 105d 105d 0/3 auto-obsoleted due to no activity on 2025/11/25 17:18
upstream INFO: rcu detected stall in aoecmd_cfg block 1 2 1786d 1819d 0/29 auto-closed as invalid on 2021/04/09 11:08
upstream INFO: rcu detected stall in aoecmd_cfg (2) usb block 1 C done 7 458d 570d 28/29 fixed on 2024/10/22 11:57
upstream BUG: soft lockup in aoecmd_cfg (3) block 1 14 8d05h 214d 0/29 upstream: reported on 2025/04/30 11:13
upstream BUG: soft lockup in aoecmd_cfg (2) block 1 3 362d 394d 0/29 auto-obsoleted due to no activity on 2025/03/02 19:34
upstream BUG: soft lockup in aoecmd_cfg block 1 1 682d 678d 0/29 auto-obsoleted due to no activity on 2024/04/17 16:28

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-....: (1 GPs behind) idle=cdd/1/0x4000000000000000 softirq=14233/14234 fqs=3819 
	(t=10500 jiffies g=17909 q=1954)
NMI backtrace for cpu 0
CPU: 0 PID: 6178 Comm: syz.0.374 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x6d8/0x1110 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1108
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:orc_ip arch/x86/kernel/unwind_orc.c:30 [inline]
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:52 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:178 [inline]
RIP: 0010:unwind_next_frame+0x1065/0x1d90 arch/x86/kernel/unwind_orc.c:448
Code: e8 3f 48 01 c8 48 83 e0 fe 4d 8d 74 45 00 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 75 27 49 63 06 <4c> 01 f0 49 8d 4e 04 48 39 e8 4c 0f 46 e9 49 8d 46 fc 4c 0f 47 e0
RSP: 0018:ffffc90000007528 EFLAGS: 00000246
RAX: fffffffffbd6fac1 RBX: ffffc900000075e8 RCX: dffffc0000000000
RDX: ffffffff8ddbe1ec RSI: ffffffff8e7989b2 RDI: 0000000000000001
RBP: ffffffff89b2dccb R08: 0000000000000011 R09: 0000000000000013
R10: fffff52000000ec9 R11: 1ffff92000000ec7 R12: ffffffff8ddbe22c
R13: ffffffff8ddbe1ec R14: ffffffff8ddbe20c R15: ffffffff8ddbe1ec
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x9c/0xd0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 kmem_cache_alloc_node+0x12d/0x2d0 mm/slub.c:3261
 __alloc_skb+0xf4/0x750 net/core/skbuff.c:415
 alloc_skb include/linux/skbuff.h:1162 [inline]
 new_skb drivers/block/aoe/aoecmd.c:67 [inline]
 aoecmd_cfg_pkts drivers/block/aoe/aoecmd.c:431 [inline]
 aoecmd_cfg+0x259/0x8c0 drivers/block/aoe/aoecmd.c:1371
 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451
 expire_timers kernel/time/timer.c:1496 [inline]
 __run_timers+0x525/0x7c0 kernel/time/timer.c:1767
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
 handle_softirqs+0x328/0x820 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:finish_lock_switch+0x134/0x280 kernel/sched/core.c:4804
Code: be ff ff ff ff e8 7c fc 55 08 85 c0 74 4a 4d 85 ff 75 66 0f 1f 44 00 00 48 89 df e8 76 67 5f 08 e8 11 76 2a 00 fb 48 83 c4 08 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 d9 0f fe ff 43 80 3c
RSP: 0018:ffffc90004267428 EFLAGS: 00000286
RAX: 145104b1e180ff00 RBX: ffff8880b903a340 RCX: 145104b1e180ff00
RDX: dffffc0000000000 RSI: ffffffff8a0b1c60 RDI: ffffffff8a59e580
RBP: 1ffff11017207613 R08: dffffc0000000000 R09: fffffbfff1ff7c2c
R10: fffffbfff1ff7c2c R11: 1ffffffff1ff7c2b R12: 1ffff110172075c1
R13: dffffc0000000000 R14: ffff8880b903ae08 R15: 0000000000000000
 finish_task_switch+0x12f/0x640 kernel/sched/core.c:4921
 context_switch kernel/sched/core.c:5052 [inline]
 __schedule+0x11c3/0x4390 kernel/sched/core.c:6395
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571
 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6596
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
 _raw_spin_unlock_irq+0x3c/0x40 kernel/locking/spinlock.c:202
 spin_unlock_irq include/linux/spinlock.h:414 [inline]
 shmem_add_to_page_cache+0xff4/0x14b0 mm/shmem.c:752
 shmem_getpage_gfp+0x1793/0x2d40 mm/shmem.c:1940
 shmem_getpage mm/shmem.c:151 [inline]
 shmem_write_begin+0xcd/0x1a0 mm/shmem.c:2474
 generic_perform_write+0x2aa/0x530 mm/filemap.c:3785
 __generic_file_write_iter+0x25f/0x4e0 mm/filemap.c:3912
 generic_file_write_iter+0xa6/0x1b0 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2173 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x712/0xd00 fs/read_write.c:594
 ksys_write+0x14d/0x250 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f54b85db749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f54b6842038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f54b8831fa0 RCX: 00007f54b85db749
RDX: 0000000000040010 RSI: 0000200000000180 RDI: 0000000000000068
RBP: 00007f54b865ff91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f54b8832038 R14: 00007f54b8831fa0 R15: 00007fffcab07608
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/26 13:18 linux-5.15.y cc5ec8769306 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in aoecmd_cfg
* Struck through repros no longer work on HEAD.