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INFO: task hung in ppp_release

Status: auto-obsoleted due to no activity on 2024/09/18 07:06
Reported-by: syzbot+e14d06db93a1e1fe1bf4@syzkaller.appspotmail.com
First crash: 727d, last: 727d
▶ ▼ Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in ppp_release 1 1 733d 733d 0/3 auto-obsoleted due to no activity on 2024/09/12 19:28
upstream INFO: task hung in ppp_release (3) ppp 1 13 700d 756d 0/29 auto-obsoleted due to no activity on 2024/09/10 18:31
upstream INFO: task hung in ppp_release (5) ppp 1 1 502d 502d 0/29 auto-obsoleted due to no activity on 2025/04/21 19:30
upstream INFO: task hung in ppp_release ppp 1 1 2199d 2199d 0/29 auto-closed as invalid on 2020/08/28 19:07
upstream INFO: task hung in ppp_release (2) ppp 1 1 1727d 1727d 0/29 auto-closed as invalid on 2021/12/13 06:07
linux-6.6 INFO: task hung in ppp_release 1 1 57d 57d 0/2 upstream: reported on 2026/04/11 00:01
upstream INFO: task hung in ppp_release (4) ppp 1 22 588d 624d 0/29 auto-obsoleted due to no activity on 2024/12/16 17:48
android-49 INFO: task hung in ppp_release 1 1 2614d 2611d 0/3 auto-closed as invalid on 2019/10/08 10:46

Sample crash report:
INFO: task syz-executor.4:8384 blocked for more than 143 seconds.
      Not tainted 6.1.92-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4  state:D stack:24464 pid:8384  ppid:6045   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
 ppp_release+0x86/0x1f0 drivers/net/ppp/ppp_generic.c:405
 __fput+0x3b7/0x890 fs/file_table.c:320
 task_work_run+0x246/0x300 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7efcc687be5a
RSP: 002b:00007ffe6d4eed60 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 00007efcc687be5a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000006
RBP: 00007efcc69b5980 R08: 000000008a844205 R09: 0000000000000010
R10: 000000000000010b R11: 0000000000000293 R12: 000000000004cbeb
R13: 00007efcc69b405c R14: 0000000000000032 R15: 00007efcc69b5980
 </TASK>
INFO: task syz-executor.0:8397 blocked for more than 143 seconds.
      Not tainted 6.1.92-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:27320 pid:8397  ppid:6138   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
 rtnl_lock net/core/rtnetlink.c:74 [inline]
 rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/10 07:05 linux-6.1.y 88690811da69 82c05ab8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in ppp_release
* Struck through repros no longer work on HEAD.