WARNING in cancel_delayed_work_sync (2)

Status: upstream: reported on 2026/08/17 20:47
Subsystems: mmc
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+c40b1b2a25a7801239d2@syzkaller.appspotmail.com
First crash: 29d, last: 16h10m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
da352467 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in cancel_delayed_work_sync (2) 2026/08/15 01:04 2026/08/15 01:04 2026/08/15 01:41 746171ee
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [mmc?] WARNING in cancel_delayed_work_sync (2) 0 (1) 2026/08/17 20:47
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in cancel_delayed_work_sync bluetooth -1 1 1415d 1411d 0/29 closed as dup on 2022/10/31 11:09

Sample crash report:
------------[ cut here ]------------
do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff8964266d>] snd_rawmidi_write+0x44d/0xc60 sound/core/rawmidi.c:1617
WARNING: kernel/sched/core.c:9179 at __might_sleep+0x94/0xc0 kernel/sched/core.c:9179, CPU#0: syz.2.77/6099
Modules linked in:
CPU: 0 UID: 0 PID: 6099 Comm: syz.2.77 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
RIP: 0010:__might_sleep+0x97/0xc0 kernel/sched/core.c:9179
Code: 8b 94 24 a8 18 00 00 48 85 d2 75 14 48 83 c4 08 89 ee 48 89 df 31 d2 5b 5d 41 5c e9 33 fc ff ff 48 8d 3d fc 2e 71 0f 48 89 d1 <67> 48 0f b9 3a eb db e8 dd 59 a8 00 eb 9f 89 74 24 04 e8 02 5a a8
RSP: 0018:ffffc90000007bd8 EFLAGS: 00010282
RAX: dffffc0000000000 RBX: ffffffff8bedf2a0 RCX: ffffffff8964266d
RDX: ffffffff8964266d RSI: 0000000000000001 RDI: ffffffff91482640
RBP: 00000000000011d1 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88807a40a580
R13: 8000000000000101 R14: 1ffff92000000f8d R15: ffffffff88c97a80
FS:  00007fb67627e6c0(0000) GS:ffff888123b5a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c40071d CR3: 000000007dfb0000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __cancel_work_sync kernel/workqueue.c:4561 [inline]
 cancel_delayed_work_sync+0xb8/0xf0 kernel/workqueue.c:4642
 mmc_free_host+0x19/0x30 drivers/mmc/core/host.c:700
 vub300_delete drivers/mmc/host/vub300.c:379 [inline]
 kref_put include/linux/kref.h:65 [inline]
 vub300_inactivity_timer_expired drivers/mmc/host/vub300.c:747 [inline]
 vub300_inactivity_timer_expired+0x42f/0x550 drivers/mmc/host/vub300.c:742
 call_timer_fn+0x198/0x5f0 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers+0x757/0xb00 kernel/time/timer.c:2374
 __run_timer_base kernel/time/timer.c:2386 [inline]
 __run_timer_base kernel/time/timer.c:2378 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2395
 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2405
 handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
 __do_softirq kernel/softirq.c:679 [inline]
 invoke_softirq kernel/softirq.c:519 [inline]
 __irq_exit_rcu+0x16a/0x210 kernel/softirq.c:758
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:220 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:229
Code: 90 f3 0f 1e fa 53 48 8b 74 24 08 48 89 fb 48 83 c7 18 e8 7a e3 13 f6 48 89 df e8 02 3a 14 f6 e8 1d fe 40 f6 fb bf 01 00 00 00 <e8> 62 2f 03 f6 65 48 83 3d 81 f5 b8 08 00 74 06 5b c3 cc cc cc cc
RSP: 0018:ffffc90004177b18 EFLAGS: 00000202
RAX: 000000000001e491 RBX: ffff888033869938 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff8e3ede41 RDI: 0000000000000001
RBP: ffff88807a40a580 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffc90004177bb8
R13: ffffffff8964266d R14: 000000000000a19c R15: ffff8880369f5058
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 snd_rawmidi_write+0x488/0xc60 sound/core/rawmidi.c:1618
 do_loop_readv_writev fs/read_write.c:851 [inline]
 do_loop_readv_writev fs/read_write.c:836 [inline]
 vfs_writev+0x5ed/0xdd0 fs/read_write.c:1060
 do_writev+0x28a/0x340 fs/read_write.c:1104
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb67539e159
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:00007fb67627e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007fb675625fa0 RCX: 00007fb67539e159
RDX: 0000000000000002 RSI: 0000200000000840 RDI: 000000000000000a
RBP: 00007fb67543503b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb675626038 R14: 00007fb675625fa0 R15: 00007ffc9de35cf8
 </TASK>
----------------
Code disassembly (best guess):
   0:	8b 94 24 a8 18 00 00 	mov    0x18a8(%rsp),%edx
   7:	48 85 d2             	test   %rdx,%rdx
   a:	75 14                	jne    0x20
   c:	48 83 c4 08          	add    $0x8,%rsp
  10:	89 ee                	mov    %ebp,%esi
  12:	48 89 df             	mov    %rbx,%rdi
  15:	31 d2                	xor    %edx,%edx
  17:	5b                   	pop    %rbx
  18:	5d                   	pop    %rbp
  19:	41 5c                	pop    %r12
  1b:	e9 33 fc ff ff       	jmp    0xfffffc53
  20:	48 8d 3d fc 2e 71 0f 	lea    0xf712efc(%rip),%rdi        # 0xf712f23
  27:	48 89 d1             	mov    %rdx,%rcx
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	eb db                	jmp    0xc
  31:	e8 dd 59 a8 00       	call   0xa85a13
  36:	eb 9f                	jmp    0xffffffd7
  38:	89 74 24 04          	mov    %esi,0x4(%rsp)
  3c:	e8                   	.byte 0xe8
  3d:	02 5a a8             	add    -0x58(%rdx),%bl

Crashes (122):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/10 10:12 upstream 50d05c7c76c9 4e8b1cc6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in cancel_delayed_work_sync
2026/09/09 06:32 upstream 893e11787f78 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in cancel_delayed_work_sync
2026/09/07 00:16 upstream 2beb1b31a12b 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in cancel_delayed_work_sync
2026/09/04 09:08 upstream 841e384b841a 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in cancel_delayed_work_sync
2026/09/03 23:51 upstream 841e384b841a 6a988719 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in cancel_delayed_work_sync
2026/08/16 15:17 upstream 3eb40771c00a 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in cancel_delayed_work_sync
2026/09/08 10:30 upstream 28924df2a08f 351387c4 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in cancel_delayed_work_sync
2026/09/11 04:48 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing ed2050bc671b 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/10 22:07 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 8d70a378e702 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/10 12:07 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/10 05:41 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 4e8b1cc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/09 09:47 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/09 05:13 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/09 04:12 linux-next 9d80aa4617b3 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in cancel_delayed_work_sync
2026/09/09 00:36 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/08 22:24 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/08 20:34 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/08 16:04 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/08 11:45 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/08 00:45 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/07 23:23 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/07 21:04 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/07 20:50 linux-next 9d80aa4617b3 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in cancel_delayed_work_sync
2026/09/07 15:45 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 34c9c5517033 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/06 22:16 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/06 10:26 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/06 06:23 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/06 01:41 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/05 22:07 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/05 13:27 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/05 06:15 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/05 03:25 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/04 23:04 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 4f7b22a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/04 20:22 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 f65209a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/04 19:34 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 f65209a4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/04 06:50 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/04 01:32 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/02 14:48 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 85995287 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/02 13:21 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 85995287 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/02 06:16 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/02 02:16 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing edc1518454f6 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/09/01 11:12 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 5704a4065c2c 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/08/31 19:45 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing cee9395acd80 316d9396 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/08/31 14:31 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing cee9395acd80 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/08/31 07:42 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 45c13f3f9e3b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/08/31 01:57 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 45c13f3f9e3b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/08/30 19:08 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 45c13f3f9e3b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/08/30 17:03 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 45c13f3f9e3b 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/08/14 19:04 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing bdab5605259b 6f9b3e89 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
2026/08/13 20:46 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 5d5fd841c346 b13552fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb WARNING in cancel_delayed_work_sync
* Struck through repros no longer work on HEAD.