syzbot


INFO: task hung in p9_fd_close

Status: upstream: reported C repro on 2019/08/19 15:52
Reported-by: syzbot+cb1a7299534706f76d88@syzkaller.appspotmail.com
First crash: 1095d, last: 23d

Fix bisection: failed (bisect log)
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in p9_fd_close C error error 333 3d03h 1083d 0/23 upstream: reported C repro on 2019/08/30 19:28
linux-4.14 INFO: task hung in p9_fd_close C inconclusive 63 64d 1103d 0/1 upstream: reported C repro on 2019/08/11 15:06
upstream INFO: task can't die in p9_fd_close C done 58 115d 722d 0/23 upstream: reported C repro on 2020/08/26 10:38

Sample crash report:
INFO: task syz-executor158:8221 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor158 D27400  8221   8138 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_timeout+0x92d/0xfe0 kernel/time/timer.c:1794
 do_wait_for_common kernel/sched/completion.c:83 [inline]
 __wait_for_common kernel/sched/completion.c:104 [inline]
 wait_for_common+0x29c/0x470 kernel/sched/completion.c:115
 __flush_work+0x4bb/0x8b0 kernel/workqueue.c:2926
 __cancel_work_timer+0x412/0x590 kernel/workqueue.c:3013
 p9_conn_destroy net/9p/trans_fd.c:899 [inline]
 p9_fd_close+0x29c/0x520 net/9p/trans_fd.c:934
 p9_client_create+0x901/0x12e0 net/9p/client.c:1084
 v9fs_session_init+0x1dd/0x1770 fs/9p/v9fs.c:421
 v9fs_mount+0x73/0x910 fs/9p/vfs_super.c:135
 mount_fs+0xa3/0x310 fs/super.c:1261
 vfs_kern_mount.part.0+0x68/0x470 fs/namespace.c:961
 vfs_kern_mount fs/namespace.c:951 [inline]
 do_new_mount fs/namespace.c:2492 [inline]
 do_mount+0x115c/0x2f50 fs/namespace.c:2822
 ksys_mount+0xcf/0x130 fs/namespace.c:3038
 __do_sys_mount fs/namespace.c:3052 [inline]
 __se_sys_mount fs/namespace.c:3049 [inline]
 __x64_sys_mount+0xba/0x150 fs/namespace.c:3049
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f3351de8359
Code: Bad RIP value.
RSP: 002b:00007f3351d74278 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3351e6d4f0 RCX: 00007f3351de8359
RDX: 0000000020000080 RSI: 0000000020000300 RDI: 0000000000000000
RBP: 00007f3351e3a0bc R08: 0000000020000740 R09: 65732f636f72702f
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3351d74280
R13: 7277732f7665642f R14: 64663d736e617274 R15: 00007f3351e6d4f8

Showing all locks held in the system:
2 locks held by kworker/0:1/14:
 #0: 00000000e305f09a ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124
 #1: 000000003e9ac0c2 ((work_completion)(&m->rq)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128
1 lock held by khungtaskd/1570:
 #0: 00000000eca63a1d (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
1 lock held by in:imklog/7824:
 #0: 0000000040d68714 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767

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

NMI backtrace for cpu 1
CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x991/0xe60 kernel/hung_task.c:287
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4690 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:check_kcov_mode kernel/kcov.c:67 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x14/0x50 kernel/kcov.c:101
Code: 35 00 e9 23 fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 8b 34 24 65 48 8b 04 25 c0 df 01 00 65 8b 15 cc 59 9f 7e <81> e2 00 01 1f 00 75 2b 8b 90 60 13 00 00 83 fa 02 75 20 48 8b 88
RSP: 0018:ffff8880a139fa28 EFLAGS: 00000246
RAX: ffff8880a1394500 RBX: dffffc0000000000 RCX: ffffffff816c5cc8
RDX: 0000000080000000 RSI: ffffffff816c36e5 RDI: ffffc90001b12072
RBP: ffff8880a139fb00 R08: 0000000000000000 R09: 0000000000000015
R10: 0000000000000006 R11: 0000000000000000 R12: ffffffff886fb460
R13: ffffed1014273f62 R14: ffffc90001b121e0 R15: 0000000040000000
FS:  00007f293b3f08c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f29387c9000 CR3: 00000000a1186000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ___bpf_prog_run+0x45/0x4e80 kernel/bpf/core.c:1065
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	e9 23 fe ff ff       	jmpq   0xfffffe28
   5:	90                   	nop
   6:	90                   	nop
   7:	90                   	nop
   8:	90                   	nop
   9:	90                   	nop
   a:	90                   	nop
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	48 8b 34 24          	mov    (%rsp),%rsi
  18:	65 48 8b 04 25 c0 df 	mov    %gs:0x1dfc0,%rax
  1f:	01 00
  21:	65 8b 15 cc 59 9f 7e 	mov    %gs:0x7e9f59cc(%rip),%edx        # 0x7e9f59f4
* 28:	81 e2 00 01 1f 00    	and    $0x1f0100,%edx <-- trapping instruction
  2e:	75 2b                	jne    0x5b
  30:	8b 90 60 13 00 00    	mov    0x1360(%rax),%edx
  36:	83 fa 02             	cmp    $0x2,%edx
  39:	75 20                	jne    0x5b
  3b:	48                   	rex.W
  3c:	8b                   	.byte 0x8b
  3d:	88                   	.byte 0x88

Crashes (110):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-19 2022/06/04 17:07 linux-4.19.y 3f8a27f9e27b c8857892 .config log report syz C INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/03/04 00:04 linux-4.19.y 3f8a27f9e27b 45a13a73 .config log report syz C INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/12/27 00:36 linux-4.19.y 3f8a27f9e27b e4f103c4 .config log report syz C INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/03/08 12:56 linux-4.19.y 2cae3e25b706 09fbf400 .config log report syz C INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/05/22 01:43 linux-4.19.y 3c8c23092588 3c7fef33 .config log report syz INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/01/15 14:40 linux-4.19.y 675cc038067f 65a7a854 .config log report syz
ci2-linux-4-19 2021/01/01 07:19 linux-4.19.y 3207316b3bee 79264ae3 .config log report syz
ci2-linux-4-19 2020/12/30 21:16 linux-4.19.y 3207316b3bee ecb8c012 .config log report syz
ci2-linux-4-19 2020/12/28 09:36 linux-4.19.y 13d2ce42de8c 2242f77f .config log report syz
ci2-linux-4-19 2020/12/28 01:58 linux-4.19.y 13d2ce42de8c 2242f77f .config log report syz
ci2-linux-4-19 2020/12/24 14:01 linux-4.19.y 13d2ce42de8c c2c1d1dd .config log report syz
ci2-linux-4-19 2020/12/16 18:00 linux-4.19.y 13d2ce42de8c 649595c6 .config log report syz
ci2-linux-4-19 2020/11/28 18:23 linux-4.19.y 0c88e405c97e 3c7136c0 .config log report syz
ci2-linux-4-19 2019/09/09 18:06 linux-4.19.y e7d2672c66e4 a60cb4cd .config log report syz
ci2-linux-4-19 2019/08/29 13:30 linux-4.19.y 97ab07e11fbf cd626f3b .config log report syz
ci2-linux-4-19 2022/07/26 01:46 linux-4.19.y 3f8a27f9e27b 34795c51 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/07/15 09:22 linux-4.19.y 3f8a27f9e27b 5d921b08 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/07/14 12:15 linux-4.19.y 3f8a27f9e27b 5d921b08 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/07/10 06:57 linux-4.19.y 3f8a27f9e27b b5765a15 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/07/06 09:39 linux-4.19.y 3f8a27f9e27b bff65f44 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/06/04 02:36 linux-4.19.y 3f8a27f9e27b c8857892 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/06/03 00:40 linux-4.19.y 3f8a27f9e27b 02dddea8 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/05/28 12:36 linux-4.19.y 3f8a27f9e27b a46af346 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/05/24 12:55 linux-4.19.y 3f8a27f9e27b fcfad4ff .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/05/18 09:55 linux-4.19.y 3f8a27f9e27b 744a39e2 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/05/02 04:17 linux-4.19.y 3f8a27f9e27b 2df221f6 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/04/25 14:30 linux-4.19.y 3f8a27f9e27b 131df97d .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/04/17 22:26 linux-4.19.y 3f8a27f9e27b 8bcc32a6 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/04/13 08:32 linux-4.19.y 3f8a27f9e27b faabdb86 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/04/08 01:02 linux-4.19.y 3f8a27f9e27b c6ff3e05 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/04/05 19:42 linux-4.19.y 3f8a27f9e27b 0127c10f .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/03/30 15:06 linux-4.19.y 3f8a27f9e27b 42718dd6 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/03/26 15:48 linux-4.19.y 3f8a27f9e27b 89bc8608 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/03/11 16:20 linux-4.19.y 3f8a27f9e27b 9e8eaa75 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/02/28 22:20 linux-4.19.y 3f8a27f9e27b 45a13a73 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/02/18 12:02 linux-4.19.y 3f8a27f9e27b 3cd800e4 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/02/12 13:42 linux-4.19.y 3f8a27f9e27b 8b9ca619 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/02/12 11:24 linux-4.19.y 3f8a27f9e27b 8b9ca619 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/02/08 09:44 linux-4.19.y 3f8a27f9e27b a7dab638 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/02/05 06:14 linux-4.19.y 3f8a27f9e27b e13a05ed .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/01/31 17:15 linux-4.19.y 3f8a27f9e27b a491ad2d .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/01/17 16:16 linux-4.19.y 3f8a27f9e27b 731a2d23 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/01/16 14:41 linux-4.19.y 3f8a27f9e27b 723cfaf0 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/01/10 07:15 linux-4.19.y 3f8a27f9e27b 2ca0d385 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2022/01/08 20:15 linux-4.19.y 3f8a27f9e27b 2ca0d385 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/12/12 16:26 linux-4.19.y 3f8a27f9e27b 49ca1f59 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/11/28 16:32 linux-4.19.y 3f8a27f9e27b 63eeac02 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/11/27 15:39 linux-4.19.y 3f8a27f9e27b 63eeac02 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/11/13 05:30 linux-4.19.y 3f8a27f9e27b 75b04091 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/11/02 00:33 linux-4.19.y 3f8a27f9e27b 098b5d53 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/11/01 12:48 linux-4.19.y 3f8a27f9e27b 098b5d53 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/10/25 07:57 linux-4.19.y 3f8a27f9e27b 4f0000ee .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/10/01 08:35 linux-4.19.y c2276d585654 1d849ab4 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/09/18 15:42 linux-4.19.y b172b44fcb17 70b76c1d .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/09/06 07:21 linux-4.19.y b172b44fcb17 d236a457 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/08/30 23:37 linux-4.19.y e23d55af0e1f 8f58a0ef .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/08/22 00:44 linux-4.19.y 59456c9cc40c b599f2fc .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/07/26 14:20 linux-4.19.y 4938296e03bd fd511809 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/07/26 06:19 linux-4.19.y 4938296e03bd fd511809 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/07/25 16:35 linux-4.19.y 4938296e03bd 4d1b57d4 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/07/23 10:14 linux-4.19.y 4938296e03bd bc5f1d88 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/07/16 21:01 linux-4.19.y fcfbdfe9626e f115ae98 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/07/10 18:03 linux-4.19.y 9f84340f012e 8f5a7b8c .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/07/06 09:50 linux-4.19.y 9f84340f012e 6c4484eb .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/07/04 10:15 linux-4.19.y 9f84340f012e 55aa55c2 .config log report info INFO: task hung in p9_fd_close
ci2-linux-4-19 2021/01/03 06:42 linux-4.19.y 3207316b3bee 79264ae3 .config log report info
ci2-linux-4-19 2019/08/19 14:51 linux-4.19.y a5aa80588fcd b8ceabfc .config log report