INFO: task hung in userfaultfd_release (2)

Status: auto-obsoleted due to no activity on 2024/09/11 05:27
Subsystems: mm fs
[Documentation on labels]
First crash: 802d, last: 802d
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in userfaultfd_release 1 1 278d 278d 0/3 auto-obsoleted due to no activity on 2026/02/27 14:18
upstream INFO: task hung in userfaultfd_release fs mm 1 1 1406d 1406d 0/29 auto-obsoleted due to no activity on 2022/12/17 09:56

Sample crash report:
INFO: task syz-executor.3:5190 blocked for more than 155 seconds.
      Not tainted 6.10.0-rc3-syzkaller-00022-gcea2a26553ac #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:24656 pid:5190  tgid:5190  ppid:5129   flags:0x00000006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6837
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
 __down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306
 mmap_write_lock include/linux/mmap_lock.h:106 [inline]
 userfaultfd_release+0x206/0x900 fs/userfaultfd.c:892
 __fput+0x406/0x8b0 fs/file_table.c:422
 task_work_run+0x24f/0x310 kernel/task_work.c:180
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6b8027cea9
RSP: 002b:00007f6b804dfb88 EFLAGS: 00000246
 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f6b803b5980 RCX: 00007f6b8027cea9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f6b803b5980 R08: 0000000081356ecd R09: 0000001d00000000
R10: 0000001b33920000 R11: 0000000000000246 R12: 000000000001618e
R13: 00007f6b803b412c R14: 0000000000000032 R15: 00007f6b803b5980
 </TASK>
INFO: task syz-executor.3:5192 blocked for more than 156 seconds.
      Not tainted 6.10.0-rc3-syzkaller-00022-gcea2a26553ac #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:26736 pid:5192  tgid:5190  ppid:5129   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5408 [inline]
 __schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
 __schedule_loop kernel/sched/core.c:6822 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6837
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/13 05:25 upstream cea2a26553ac 2aa5052f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce INFO: task hung in userfaultfd_release
* Struck through repros no longer work on HEAD.