syzbot


WARNING in call_timer_fn (2)

Status: upstream: reported on 2025/05/20 15:59
Reported-by: syzbot+97c9d96f4cf6e2f67ce5@syzkaller.appspotmail.com
First crash: 10d, last: 2d03h
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in call_timer_fn bluetooth C unreliable 6807 1h24m 926d 0/28 upstream: reported C repro on 2022/11/16 15:25
linux-6.1 WARNING in call_timer_fn origin:lts-only C unreliable 166 2d16h 814d 0/3 upstream: reported C repro on 2023/03/08 12:11
linux-5.15 WARNING in call_timer_fn origin:lts-only syz unreliable 7 209d 465d 0/3 auto-obsoleted due to no activity on 2025/02/11 06:36

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4815 at kernel/workqueue.c:1453 __queue_work+0xc04/0xd50 kernel/workqueue.c:1453
Modules linked in:
CPU: 1 PID: 4815 Comm: syz.0.131 Not tainted 5.15.184-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__queue_work+0xc04/0xd50 kernel/workqueue.c:1453
Code: fc ff ff 48 8b 4c 24 08 80 e1 07 80 c1 03 38 c1 0f 8c 13 fd ff ff 48 8b 7c 24 08 e8 f6 34 70 00 e9 04 fd ff ff e8 2c bf 2a 00 <0f> 0b 48 83 c4 50 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 16 bf 2a 00
RSP: 0018:ffffc90000dd0b18 EFLAGS: 00010046
RAX: ffffffff814d0214 RBX: 0000000000010000 RCX: ffff888027749dc0
RDX: 0000000000000100 RSI: 0000000000000100 RDI: 0000000000000000
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1ad1556
R10: fffffbfff1ad1556 R11: 1ffffffff1ad1555 R12: ffff8880183fa180
R13: ffff88801a9c69c0 R14: ffff88801a9c6800 R15: 0000000000000008
FS:  00007f04b1d8c6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30a1dff8 CR3: 00000000667b7000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 call_timer_fn+0x16c/0x530 kernel/time/timer.c:1451
 expire_timers kernel/time/timer.c:1491 [inline]
 __run_timers+0x550/0x7c0 kernel/time/timer.c:1767
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780
 handle_softirqs+0x328/0x820 kernel/softirq.c:558
 __do_softirq kernel/softirq.c:592 [inline]
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:641
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653
 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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f6 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ce d9 b1 f7 48 89 df e8 96 ae b2 f7 e8 d1 52 d3 f7 fb bf 01 00 00 00 <e8> c6 d2 a6 f7 65 8b 05 37 e3 57 76 85 c0 74 02 5b c3 e8 e4 ed 55
RSP: 0018:ffffc900032df600 EFLAGS: 00000286
RAX: 190ace8620d35800 RBX: ffff88807d5cd710 RCX: 190ace8620d35800
RDX: dffffc0000000000 RSI: ffffffff8a0b11c0 RDI: 0000000000000001
RBP: ffffc900032df7bc R08: dffffc0000000000 R09: fffffbfff1ff361f
R10: fffffbfff1ff361f R11: 1ffffffff1ff361e R12: dffffc0000000000
R13: ffffc900032df9e8 R14: 0000000000000000 R15: 0000000000000615
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 shmem_getpage_gfp+0x1fe7/0x2d40 mm/shmem.c:1951
 shmem_fault+0x1a9/0x520 mm/shmem.c:2118
 __do_fault+0x141/0x330 mm/memory.c:3928
 do_read_fault mm/memory.c:4264 [inline]
 do_fault mm/memory.c:4392 [inline]
 handle_pte_fault mm/memory.c:4650 [inline]
 __handle_mm_fault mm/memory.c:4785 [inline]
 handle_mm_fault+0x2949/0x43c0 mm/memory.c:4883
 faultin_page mm/gup.c:976 [inline]
 __get_user_pages+0x93e/0x11c0 mm/gup.c:1197
 populate_vma_page_range+0x213/0x290 mm/gup.c:1529
 __mm_populate+0x26f/0x3a0 mm/gup.c:1638
 mm_populate include/linux/mm.h:2632 [inline]
 vm_mmap_pgoff+0x203/0x2b0 mm/util.c:556
 ksys_mmap_pgoff+0x140/0x780 mm/mmap.c:1623
 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: 0033:0x7f04b3f24969
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:00007f04b1d8c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f04b414bfa0 RCX: 00007f04b3f24969
RDX: b635773f06ebbeef RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f04b3fa6ab1 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f04b414bfa0 R15: 00007fff58b52ee8
 </TASK>
----------------
Code disassembly (best guess):
   0:	f6 ff                	idiv   %bh
   2:	0f 1f 00             	nopl   (%rax)
   5:	53                   	push   %rbx
   6:	48 89 fb             	mov    %rdi,%rbx
   9:	48 83 c7 18          	add    $0x18,%rdi
   d:	48 8b 74 24 08       	mov    0x8(%rsp),%rsi
  12:	e8 ce d9 b1 f7       	call   0xf7b1d9e5
  17:	48 89 df             	mov    %rbx,%rdi
  1a:	e8 96 ae b2 f7       	call   0xf7b2aeb5
  1f:	e8 d1 52 d3 f7       	call   0xf7d352f5
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 c6 d2 a6 f7       	call   0xf7a6d2f5 <-- trapping instruction
  2f:	65 8b 05 37 e3 57 76 	mov    %gs:0x7657e337(%rip),%eax        # 0x7657e36d
  36:	85 c0                	test   %eax,%eax
  38:	74 02                	je     0x3c
  3a:	5b                   	pop    %rbx
  3b:	c3                   	ret
  3c:	e8                   	.byte 0xe8
  3d:	e4 ed                	in     $0xed,%al
  3f:	55                   	push   %rbp

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/29 07:46 linux-5.15.y 98f47d0e9b8c 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in call_timer_fn
2025/05/20 15:59 linux-5.15.y a68c15152131 b47f9e02 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in call_timer_fn
* Struck through repros no longer work on HEAD.