syzbot


INFO: task hung in path_openat (2)

Status: auto-obsoleted due to no activity on 2024/04/08 11:39
Reported-by: syzbot+6a49c9c38e2ef935c9ce@syzkaller.appspotmail.com
First crash: 119d, last: 119d
Similar bugs (17)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in path_openat 2 1688d 1721d 0/1 auto-closed as invalid on 2020/01/11 07:40
upstream INFO: task hung in path_openat (4) fuse 1 1459d 1459d 0/26 auto-closed as invalid on 2020/07/28 10:23
upstream INFO: task hung in path_openat (3) fs 4 1618d 1735d 0/26 auto-closed as invalid on 2020/02/19 20:16
upstream INFO: task hung in path_openat (7) fs 858 16m 569d 0/26 upstream: reported on 2022/10/06 10:29
linux-5.15 INFO: task hung in path_openat (2) 7 1d15h 13d 0/3 upstream: reported on 2024/04/14 03:45
linux-4.19 INFO: task hung in path_openat (2) 1 888d 888d 0/1 auto-closed as invalid on 2022/03/21 04:47
linux-4.14 INFO: task hung in path_openat 1 1128d 1128d 0/1 auto-closed as invalid on 2021/07/23 23:26
android-49 INFO: task hung in path_openat 64 1859d 1840d 0/3 auto-closed as invalid on 2019/09/22 08:41
upstream INFO: task hung in path_openat (5) fs 23 1099d 1260d 0/26 auto-closed as invalid on 2021/07/22 20:44
linux-4.19 INFO: task hung in path_openat (3) f2fs jfs 20 465d 624d 0/1 upstream: reported on 2022/08/11 13:14
upstream INFO: task hung in path_openat (6) fs 13 835d 985d 0/26 closed as invalid on 2022/02/07 19:19
android-414 INFO: task hung in path_openat 42 1762d 1841d 0/1 auto-closed as invalid on 2019/10/28 21:04
linux-6.1 INFO: task hung in path_openat 3 287d 389d 0/3 auto-obsoleted due to no activity on 2023/10/23 12:08
linux-6.1 INFO: task hung in path_openat (3) 10 5d11h 13d 0/3 upstream: reported on 2024/04/14 13:03
upstream INFO: task hung in path_openat exfat 246 1926d 2216d 0/26 closed as dup on 2018/09/08 15:37
linux-5.15 INFO: task hung in path_openat C error 3 269d 381d 0/3 auto-obsoleted due to no activity on 2023/11/09 20:56
upstream INFO: task hung in path_openat (2) fs 1 1829d 1829d 0/26 closed as invalid on 2019/05/08 13:05

Sample crash report:
INFO: task syz-executor.0:18064 blocked for more than 143 seconds.
      Not tainted 6.1.69-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:28312 pid:18064 ppid:3588   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
 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189
 inode_lock include/linux/fs.h:756 [inline]
 open_last_lookups fs/namei.c:3479 [inline]
 path_openat+0x7b6/0x2e60 fs/namei.c:3712
 do_filp_open+0x230/0x480 fs/namei.c:3742
 do_sys_openat2+0x13b/0x500 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_open fs/open.c:1342 [inline]
 __se_sys_open fs/open.c:1338 [inline]
 __x64_sys_open+0x221/0x270 fs/open.c:1338
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4ce267cce9
RSP: 002b:00007f4ce11bc0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f4ce279c120 RCX: 00007f4ce267cce9
RDX: 0000000000000000 RSI: 000000000014d27e RDI: 0000000020000180
RBP: 00007f4ce26c947a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f4ce279c120 R15: 00007ffedf998a98
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d12a4f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d12acf0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by khungtaskd/28:
 #0: ffffffff8d12a320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline]
 #0: ffffffff8d12a320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline]
 #0: ffffffff8d12a320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494
2 locks held by getty/3303:
 #0: ffff888028d5c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188
9 locks held by kworker/u4:24/5235:
2 locks held by syz-executor.0/18059:
2 locks held by syz-executor.0/18064:
 #0: ffff8880277c4460 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #1: ffff8880aa2a5c20 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
 #1: ffff8880aa2a5c20 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: open_last_lookups fs/namei.c:3479 [inline]
 #1: ffff8880aa2a5c20 (&type->i_mutex_dir_key#8){++++}-{3:3}, at: path_openat+0x7b6/0x2e60 fs/namei.c:3712
2 locks held by syz-executor.0/20144:

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.69-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf88/0xfd0 kernel/hung_task.c:377
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5247 Comm: kworker/u4:30 Not tainted 6.1.69-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Workqueue: bat_events batadv_nc_worker
RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4723 [inline]
RIP: 0010:__lock_acquire+0x49d/0x1f80 kernel/locking/lockdep.c:4999
Code: 12 00 00 44 89 33 44 89 fb 48 89 d8 48 c1 e8 06 48 8d 3c c5 20 f2 48 90 be 08 00 00 00 e8 1b 9b 77 00 48 0f a3 1d a3 9c de 0e <73> 25 48 8d 04 5b 48 c1 e0 06 48 8d 98 20 51 18 90 48 ba 00 00 00
RSP: 0018:ffffc9000589f900 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 00000000000006c6 RCX: ffffffff816a5575
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff9048f2f8
RBP: ffff8880742ba884 R08: dffffc0000000000 R09: fffffbfff2091e60
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880742ba898
R13: ffff8880742b9dc0 R14: 0000000000000000 R15: 00000000000006c6
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c039003000 CR3: 000000000ce8e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
 _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
 spin_lock_bh include/linux/spinlock.h:355 [inline]
 batadv_nc_purge_paths+0xe8/0x3b0 net/batman-adv/network-coding.c:442
 batadv_nc_worker+0x324/0x610 net/batman-adv/network-coding.c:720
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/12/30 11:38 linux-6.1.y 4aa6747d9352 fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in path_openat
* Struck through repros no longer work on HEAD.