syzbot

 sign-in | mailing list | source | docs
🐞 Open [1008] ≡ Subsystems 🐞 Fixed [5248] 🐞 Invalid [12550] ⬇ Missing Backports [83] 📈 Kernel Health 📈 Bug Lifetimes 📈 Fuzzing 📈 Crashes 💬 Send us feedback

INFO: rcu detected stall in __mod_timer (3)

Status: closed as invalid on 2022/02/08 10:00
Subsystems: perf
[Documentation on labels]
First crash: 1047d, last: 822d
▶ ▼ Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in __mod_timer kernel 1 1508d 1508d 0/26 auto-closed as invalid on 2020/06/13 13:03
upstream INFO: rcu detected stall in __mod_timer (2) kernel 17 1192d 1398d 0/26 auto-closed as invalid on 2021/05/17 11:36
upstream INFO: rcu detected stall in __mod_timer (4) net 1 605d 605d 0/26 auto-obsoleted due to no activity on 2022/12/03 01:18

Sample crash report:
rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (1 GPs behind) idle=531/1/0x4000000000000000 softirq=88856/88857 fqs=5245 
	(t=10502 jiffies g=145805 q=160)
NMI backtrace for cpu 1
CPU: 1 PID: 434 Comm: syz-executor.5 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343
 print_cpu_stall kernel/rcu/tree_stall.h:604 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:688 [inline]
 rcu_pending kernel/rcu/tree.c:3919 [inline]
 rcu_sched_clock_irq.cold+0x5c/0x759 kernel/rcu/tree.c:2617
 update_process_times+0x16d/0x200 kernel/time/timer.c:1785
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194
Code: 74 24 10 e8 4a bf 0d f8 48 89 ef e8 02 35 0e f8 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 43 f0 00 f8 65 8b 05 ec f0 b2 76 85 c0 74 0a 5b 5d c3 e8 e0 19
RSP: 0018:ffffc90000dc0c08 EFLAGS: 00000206
RAX: 0000000000000012 RBX: 0000000000000200 RCX: 1ffffffff200465e
RDX: 0000000000000000 RSI: 0000000000000102 RDI: 0000000000000001
RBP: ffff8880b9d28480 R08: 0000000000000001 R09: ffffffff8ffcbaef
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000100014756
R13: ffff8880b9d28480 R14: 0000000000000000 R15: 00000000ffffffff
 __mod_timer+0x837/0xe30 kernel/time/timer.c:1065
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734
 __run_timers kernel/time/timer.c:1715 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194
Code: 74 24 10 e8 4a bf 0d f8 48 89 ef e8 02 35 0e f8 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 <e8> 43 f0 00 f8 65 8b 05 ec f0 b2 76 85 c0 74 0a 5b 5d c3 e8 e0 19
RSP: 0018:ffffc900106579e0 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000200 RCX: 1ffffffff200960e
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffffffff90750760 R08: 0000000000000001 R09: ffffffff8ffcbb57
R10: 0000000000000001 R11: 0000000000000001 R12: 000000000000000e
R13: 000000000000000e R14: dead000000000100 R15: dffffc0000000000
 __debug_check_no_obj_freed lib/debugobjects.c:1002 [inline]
 debug_check_no_obj_freed+0x20c/0x420 lib/debugobjects.c:1023
 free_pages_prepare mm/page_alloc.c:1358 [inline]
 free_pcp_prepare+0x2ae/0x870 mm/page_alloc.c:1404
 free_unref_page_prepare mm/page_alloc.c:3325 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3404
 qlink_free mm/kasan/quarantine.c:157 [inline]
 qlist_free_all+0x6d/0x160 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:447
 kasan_slab_alloc include/linux/kasan.h:260 [inline]
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3230 [inline]
 __kmalloc_node+0x23a/0x390 mm/slub.c:4468
 kmalloc_node include/linux/slab.h:604 [inline]
 kzalloc_node include/linux/slab.h:726 [inline]
 rb_alloc+0xbc/0x5e0 kernel/events/ring_buffer.c:818
 perf_mmap+0xf16/0x1a50 kernel/events/core.c:6340
 call_mmap include/linux/fs.h:2091 [inline]
 mmap_region+0xd88/0x1630 mm/mmap.c:1793
 do_mmap+0x869/0xfb0 mm/mmap.c:1582
 vm_mmap_pgoff+0x1b7/0x290 mm/util.c:519
 ksys_mmap_pgoff+0x40d/0x5a0 mm/mmap.c:1630
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f998cf67059
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f998b8dc168 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f998d079f60 RCX: 00007f998cf67059
RDX: 0000000000010006 RSI: 0000000000003000 RDI: 0000000020000000
RBP: 00007f998cfc108d R08: 0000000000000003 R09: 0000000000000000
R10: 0000000000080011 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f998d5adb1f R14: 00007f998b8dc300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	24 10                	and    $0x10,%al
   2:	e8 4a bf 0d f8       	callq  0xf80dbf51
   7:	48 89 ef             	mov    %rbp,%rdi
   a:	e8 02 35 0e f8       	callq  0xf80e3511
   f:	81 e3 00 02 00 00    	and    $0x200,%ebx
  15:	75 25                	jne    0x3c
  17:	9c                   	pushfq
  18:	58                   	pop    %rax
  19:	f6 c4 02             	test   $0x2,%ah
  1c:	75 2d                	jne    0x4b
  1e:	48 85 db             	test   %rbx,%rbx
  21:	74 01                	je     0x24
  23:	fb                   	sti
  24:	bf 01 00 00 00       	mov    $0x1,%edi
* 29:	e8 43 f0 00 f8       	callq  0xf800f071 <-- trapping instruction
  2e:	65 8b 05 ec f0 b2 76 	mov    %gs:0x76b2f0ec(%rip),%eax        # 0x76b2f121
  35:	85 c0                	test   %eax,%eax
  37:	74 0a                	je     0x43
  39:	5b                   	pop    %rbx
  3a:	5d                   	pop    %rbp
  3b:	c3                   	retq
  3c:	e8                   	.byte 0xe8
  3d:	e0 19                	loopne 0x58

Crashes (24):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/01/22 00:17 upstream 9b57f4589857 214351e1 .config console log report info ci-upstream-kasan-gce INFO: rcu detected stall in __mod_timer
2022/01/07 22:49 upstream ddec8ed2d490 2ca0d385 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in __mod_timer
2021/11/26 02:13 upstream b501b85957de 63eeac02 .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in __mod_timer
2021/11/17 12:19 upstream 8ab774587903 cafff8b6 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in __mod_timer
2021/11/17 04:26 upstream 8ab774587903 cafff8b6 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in __mod_timer
2021/11/15 10:47 upstream fa55b7dcdc43 83f5c9b5 .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in __mod_timer
2021/11/05 03:58 upstream 7ddb58cb0eca 4c1be0be .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in __mod_timer
2021/11/04 20:43 upstream 7ddb58cb0eca 4c1be0be .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in __mod_timer
2021/11/01 10:34 upstream 8bb7eca972ad 098b5d53 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in __mod_timer
2021/10/23 05:24 upstream 64222515138e 282f03fb .config console log report info ci-upstream-kasan-gce-smack-root INFO: rcu detected stall in __mod_timer
2021/09/26 06:57 upstream a5e0aceabef6 8cac236e .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in __mod_timer
2021/09/02 12:21 upstream 4ac6d90867a4 15cea0a3 .config console log report info ci-upstream-kasan-gce-root INFO: rcu detected stall in __mod_timer
2021/08/24 09:58 upstream d5ae8d7f85b7 b599f2fc .config console log report info ci-upstream-kasan-gce INFO: rcu detected stall in __mod_timer
2021/08/18 04:00 upstream 794c7931a242 a2fe1cb5 .config console log report info ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in __mod_timer
2021/08/11 22:03 upstream 761c6d7ec820 6972b106 .config console log report info ci-upstream-kasan-gce INFO: rcu detected stall in __mod_timer
2021/07/26 15:42 upstream ff1176468d36 fd511809 .config console log report info ci-upstream-kasan-gce INFO: rcu detected stall in __mod_timer
2021/06/18 23:08 upstream fd0aa1a4567d aba2b2fb .config console log report info ci-upstream-kasan-gce INFO: rcu detected stall in __mod_timer
2022/01/01 06:30 upstream 4f3d93c6eaff e1768e9c .config console log report info ci-upstream-kasan-gce-386 INFO: rcu detected stall in __mod_timer
2022/01/30 17:57 bpf e2bcbd7769ee 495e00c5 .config console log report info ci-upstream-bpf-kasan-gce INFO: rcu detected stall in __mod_timer
2022/01/07 23:28 linux-next b8170452cd51 2ca0d385 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in __mod_timer
2021/12/22 11:34 linux-next 07f8c60fe60f 6caa12e4 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in __mod_timer
2021/12/16 11:17 linux-next 93bf6eee76c0 572bcb40 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in __mod_timer
2021/11/05 01:15 linux-next 8a796a1dfca2 4c1be0be .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in __mod_timer
2021/10/31 08:01 linux-next bdcc9f6a5682 098b5d53 .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in __mod_timer
* Struck through repros no longer work on HEAD.