syzbot


INFO: task hung in sync_bdevs (3)

Status: upstream: reported C repro on 2025/02/23 13:57
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+97bc0b256218ed6df337@syzkaller.appspotmail.com
First crash: 232d, last: 14m
Discussions (3)
Title Replies (including bot) Last reply
[syzbot] Monthly block report (Aug 2025) 0 (1) 2025/08/27 08:15
[syzbot] [block?] INFO: task hung in sync_bdevs (3) 0 (2) 2025/08/15 22:41
[syzbot] Monthly block report (Jul 2025) 0 (1) 2025/07/27 10:41
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in sync_bdevs 1 9 7d17h 49d 0/3 upstream: reported on 2025/07/29 07:59
upstream INFO: task hung in sync_bdevs (2) block 1 1 324d 324d 0/29 auto-obsoleted due to no activity on 2025/01/25 03:29
linux-5.15 INFO: task hung in sync_bdevs 1 1 480d 480d 0/3 auto-obsoleted due to no activity on 2024/08/31 17:12
upstream INFO: task hung in sync_bdevs block 1 5 862d 1066d 0/29 auto-obsoleted due to no activity on 2023/08/05 18:35
linux-6.6 INFO: task hung in sync_bdevs 1 33 18h51m 69d 0/2 upstream: reported on 2025/07/09 10:03

Sample crash report:
INFO: task syz-executor297:5890 blocked for more than 143 seconds.
      Not tainted 6.17.0-rc1-next-20250814-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor297 state:D stack:28168 pid:5890  tgid:5890  ppid:5887   task_flags:0x400040 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5357 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
 __mutex_lock_common kernel/locking/mutex.c:676 [inline]
 __mutex_lock+0x7e6/0x1360 kernel/locking/mutex.c:760
 sync_bdevs+0x1ac/0x340 block/bdev.c:1288
 ksys_sync+0xb9/0x150 fs/sync.c:105
 __ia32_sys_sync+0xe/0x20 fs/sync.c:113
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd97a9d2959
RSP: 002b:00007ffd0221b4d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fd97a9d2959
RDX: 00007fd97a9d1b90 RSI: 0000000000000012 RDI: 00007fd97aa1b03b
RBP: 000000000002219f R08: 0000000000000000 R09: 0000000000000006
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd0221b4ec
R13: 431bde82d7b634db R14: 0000000000000001 R15: 0000000000000001
 </TASK>
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.17.0-rc1-next-20250814-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
 watchdog+0xf60/0xfa0 kernel/hung_task.c:495
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.17.0-rc1-next-20250814-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: 53 e8 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 1a 25 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8e207d80 EFLAGS: 000002c6
RAX: 302944256c608e00 RBX: ffffffff8196d368 RCX: 302944256c608e00
RDX: 0000000000000001 RSI: ffffffff8c04d960 RDI: ffffffff8196d368
RBP: ffffffff8e207eb8 R08: ffff8880b8632f9b R09: 1ffff110170c65f3
R10: dffffc0000000000 R11: ffffed10170c65f4 R12: ffffffff8fe4db30
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff1c52a40
FS:  0000000000000000(0000) GS:ffff8881257d6000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005595b06bc168 CR3: 000000000e336000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:757
 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:190 [inline]
 do_idle+0x1e8/0x510 kernel/sched/idle.c:330
 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428
 rest_init+0x2de/0x300 init/main.c:756
 start_kernel+0x3a9/0x410 init/main.c:1109
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:307
 x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:288
 common_startup_64+0x13e/0x147
 </TASK>

Crashes (897):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/15 22:40 linux-next 931e46dcbc7e 1804e95e .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/15 21:55 upstream f83ec76bf285 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/15 13:34 upstream f83ec76bf285 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/15 12:21 upstream f83ec76bf285 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/15 06:32 upstream f83ec76bf285 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/14 11:54 upstream f83a4f2a4d8c e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/13 20:38 upstream 5cd64d4f9268 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/13 00:14 upstream 320475fbd590 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/12 21:25 upstream 320475fbd590 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/12 09:45 upstream 02ffd6f89c50 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/11 21:12 upstream 02ffd6f89c50 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/11 15:32 upstream 7aac71907bde fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/11 14:28 upstream 7aac71907bde fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/11 12:35 upstream 7aac71907bde fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/11 11:11 upstream 7aac71907bde fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/11 09:01 upstream 7aac71907bde fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/11 06:38 upstream 7aac71907bde fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/11 03:34 upstream 7aac71907bde fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/10 21:45 upstream 9dd1835ecda5 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/10 19:24 upstream 9dd1835ecda5 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/10 13:40 upstream 9dd1835ecda5 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/10 12:26 upstream 9dd1835ecda5 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/09/09 17:11 upstream f777d1112ee5 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in sync_bdevs
2025/02/23 13:55 upstream 27102b38b8ca d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root INFO: task hung in sync_bdevs
2025/02/19 13:47 upstream 6537cfb395f3 9a14138f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in sync_bdevs
2025/02/06 13:28 upstream 92514ef226f5 577d049b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root INFO: task hung in sync_bdevs
2025/09/16 13:06 linux-next c3067c2c3831 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/16 02:56 linux-next c3067c2c3831 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/15 20:40 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/15 10:56 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/15 09:56 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/15 05:15 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/15 04:36 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/15 02:35 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/14 21:34 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/14 17:39 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/14 15:10 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/14 08:17 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/14 05:30 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/14 03:20 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/14 00:39 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/13 23:08 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/13 14:26 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/13 02:42 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/12 22:19 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/12 17:45 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/12 16:30 linux-next 590b221ed425 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/12 03:53 linux-next 5f540c4aade9 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/12 00:09 linux-next 5f540c4aade9 e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/11 18:30 linux-next 5f540c4aade9 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/11 04:51 linux-next 5f540c4aade9 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in sync_bdevs
2025/09/10 18:05 linux-next 5f540c4aade9 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/10 16:11 linux-next 5f540c4aade9 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce INFO: task hung in sync_bdevs
2025/09/05 15:34 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci b320789d6883 d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in sync_bdevs
* Struck through repros no longer work on HEAD.