syzbot

 sign-in | mailing list | source | docs
🐞 Open [835]
🐞 Fixed [87]
🐞 Invalid [1228]
⬇ Missing Backports [132]
≡ Crashes
Kernel Health Bugs/Month Bug Lifetimes Fuzzing
💬 Send us feedback

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: 87d, last: 28d
▶ ▼ 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 542d 631d 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 188d 188d 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 1870d 1902d 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 541d 654d 28/29 fixed on 2024/10/22 11:57
upstream BUG: soft lockup in aoecmd_cfg (3) block 1 23 10d 298d 0/29 upstream: reported on 2025/04/30 11:13
upstream BUG: soft lockup in aoecmd_cfg (2) block 1 3 446d 478d 0/29 auto-obsoleted due to no activity on 2025/03/02 19:34
upstream BUG: soft lockup in aoecmd_cfg block 1 1 765d 761d 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=c55/1/0x4000000000000000 softirq=25022/25024 fqs=5212 
	(t=10502 jiffies g=36201 q=1784)
NMI backtrace for cpu 0
CPU: 0 PID: 9511 Comm: syz.5.1210 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 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+0x6ea/0x1120 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+0x4ad/0xb70 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:unwind_next_frame+0xa3d/0x1d90 arch/x86/kernel/unwind_orc.c:-1
Code: 48 8b 44 24 68 42 0f b6 04 28 84 c0 4c 8b 74 24 28 0f 85 40 10 00 00 41 c6 07 00 ba 10 00 00 00 4c 89 f7 31 f6 e8 b3 0e 89 00 <48> 8b 3c 24 e9 ec 04 00 00 48 89 54 24 50 48 8d 7b 08 48 89 f8 48
RSP: 0018:ffffc90000007528 EFLAGS: 00000202
RAX: ffffc90000007638 RBX: ffffc900000075e8 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90000007648
RBP: ffffc90000007630 R08: ffffc90000007647 R09: ffffc90000007638
R10: dffffc0000000000 R11: fffff52000000ec9 R12: 1ffffffff1c09ef0
R13: dffffc0000000000 R14: ffffc90000007638 R15: ffffc9000000761d
 arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa6/0xf0 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+0x282/0x910 drivers/block/aoe/aoecmd.c:1371
 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1451
 expire_timers kernel/time/timer.c:1496 [inline]
 __run_timers+0x53a/0x7f0 kernel/time/timer.c:1767
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 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:preempt_schedule_irq+0xb6/0x160 kernel/sched/core.c:6799
Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 7f bf 01 00 00 00 e8 e5 2f 8e f7 e8 70 19 bb f7 fb bf 01 00 00 00 <e8> 65 b5 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f
RSP: 0018:ffffc9000304f5e0 EFLAGS: 00000282
RAX: 91ff5cf4d1cadf00 RBX: ffff888029e88000 RCX: 91ff5cf4d1cadf00
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: 0000000000000001
RBP: ffffc9000304f690 R08: ffffffff901d10cf R09: 1ffffffff203a219
R10: dffffc0000000000 R11: fffffbfff203a21a R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000609ebc
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:check_kcov_mode kernel/kcov.c:172 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:227 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp8+0x13/0x80 kernel/kcov.c:273
Code: 4a 89 7c 02 10 4a 89 74 02 18 4a 89 44 02 20 48 ff c1 48 89 0a c3 90 48 8b 04 24 65 48 8b 0d 34 4e 89 7e 65 8b 15 35 4e 89 7e <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 34 16 00 00
RSP: 0018:ffffc9000304f758 EFLAGS: 00000203
RAX: ffffffff88635b11 RBX: 0000000000061246 RCX: ffff888029e88000
RDX: 0000000080000000 RSI: 0000000000061246 RDI: 0000000000061246
RBP: ffffc9000304f870 R08: dffffc0000000000 R09: 1ffffffff203a218
R10: dffffc0000000000 R11: fffffbfff203a219 R12: 0000000000061246
R13: dffffc0000000000 R14: ffff88814cf09230 R15: ffffffff8d617088
 inet_twsk_purge+0x5c1/0x840 net/ipv4/inet_timewait_sock.c:307
 ops_exit_list net/core/net_namespace.c:177 [inline]
 setup_net+0x844/0xa10 net/core/net_namespace.c:365
 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:503
 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
 copy_namespaces+0x37d/0x3e0 kernel/nsproxy.c:178
 copy_process+0x1834/0x3e20 kernel/fork.c:2293
 kernel_clone+0x23f/0x990 kernel/fork.c:2679
 __do_sys_clone kernel/fork.c:2796 [inline]
 __se_sys_clone kernel/fork.c:2780 [inline]
 __x64_sys_clone+0x19a/0x210 kernel/fork.c:2780
 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: 0033:0x7f9a768b6cb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9a74b11fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f9a76b31fa0 RCX: 00007f9a768b6cb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000042000000
RBP: 00007f9a76924bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f9a76b32038 R14: 00007f9a76b31fa0 R15: 00007ffcf9ff01d8
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/01/25 06:23 linux-5.15.y 9eec9a14ee10 40acda8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf INFO: rcu detected stall in aoecmd_cfg
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.