INFO: task hung in io_wq_put_and_exit

Status: premoderation: reported on 2026/09/18 05:44
Reported-by: syzbot+c7ebafb68ac7813310d4@syzkaller.appspotmail.com
First crash: 3d12h, last: 3d12h
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in io_wq_put_and_exit (6) io-uring 1 syz, C error 74 240d 399d 29/29 fixed on 2026/05/06 16:40
linux-5.15 INFO: task hung in io_wq_put_and_exit 1 1 924d 924d 0/3 auto-obsoleted due to no activity on 2024/06/19 08:55
linux-6.6 INFO: task hung in io_wq_put_and_exit origin:lts-only 1 syz, C done 17 38d 452d 0/2 upstream: reported C repro on 2025/06/25 22:50
upstream INFO: task hung in io_wq_put_and_exit (3) io-uring 1 syz, C error unreliable 75 1248d 1643d 0/29 auto-obsoleted due to no activity on 2023/08/20 08:26
upstream INFO: task hung in io_wq_put_and_exit io-uring fs 1 syz, C unreliable 628 1777d 1838d 20/29 fixed on 2021/11/10 00:50
upstream INFO: task hung in io_wq_put_and_exit (2) fs 1 22 1746d 1775d 0/29 closed as invalid on 2022/02/08 09:40
upstream INFO: task hung in io_wq_put_and_exit (5) io-uring input usb 1 syz, C done 9 406d 425d 0/29 closed as invalid on 2025/08/13 14:32
upstream INFO: task hung in io_wq_put_and_exit (4) io-uring 1 syz, C unreliable 86 472d 701d 28/29 fixed on 2025/06/10 16:19
linux-6.1 INFO: task hung in io_wq_put_and_exit 1 syz, C 4 18d 47d 0/3 upstream: reported C repro on 2026/08/04 21:15

Sample crash report:
INFO: task syz.6.2234:7931 blocked for more than 126 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.2234      state:D stack:0     pid:7931  tgid:7930  ppid:7518   flags:0x00024000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:6063 [inline]
 __schedule+0x1496/0x20b0 kernel/sched/core.c:7883
 __schedule_loop kernel/sched/core.c:7960 [inline]
 schedule+0xc5/0x240 kernel/sched/core.c:7975
 schedule_timeout+0xc7/0x3b0 kernel/time/timer.c:2596
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common+0x368/0x650 kernel/sched/completion.c:127
 wait_for_completion+0x1c/0x40 kernel/sched/completion.c:148
 io_wq_exit_workers io_uring/io-wq.c:1265 [inline]
 io_wq_put_and_exit+0x34e/0x6a0 io_uring/io-wq.c:1293
 io_uring_clean_tctx+0x117/0x190 io_uring/tctx.c:204
 io_uring_cancel_generic+0x629/0x6eb io_uring/io_uring.c:3276
 __io_uring_cancel+0x1e/0x3b io_uring/io_uring.c:3291
 io_uring_files_cancel include/linux/io_uring.h:19 [inline]
 do_exit+0x52b/0x2850 kernel/exit.c:906
 do_group_exit+0x21f/0x2f0 kernel/exit.c:1104
 get_signal+0x134c/0x1490 kernel/signal.c:2941
 arch_do_signal_or_restart+0xbc/0x700 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 irqentry_exit_to_user_mode+0x4d/0xb0 kernel/entry/common.c:231
 irqentry_exit+0x16/0x60 kernel/entry/common.c:334
 sysvec_apic_timer_interrupt+0x50/0x90 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702
RIP: 0033:0x7f81ff39e159
RSP: 002b:00007f82002fbf38 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 0000200000000340 RCX: 00007f81ff39e159
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000074
RBP: 0000000000000c3a R08: 0000000000000000 R09: 0000000000000008
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000008 R14: 0000000000000e26 R15: 0000000000000000
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/18 05:43 android16-6.12 e79b240621d0 8d7d05f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-12-rust INFO: task hung in io_wq_put_and_exit
* Struck through repros no longer work on HEAD.