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INFO: task hung in mount_bdev

Status: upstream: reported C repro on 2019/08/22 06:31
Reported-by: syzbot+c29333e4feb516181304@syzkaller.appspotmail.com
First crash: 1699d, last: 924d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 INFO: task hung in mount_bdev 1 1620d 1620d 0/1 auto-closed as invalid on 2020/03/08 13:23
upstream INFO: task hung in mount_bdev isofs 1 1950d 1950d 0/26 closed as dup on 2018/12/14 15:35
linux-4.14 INFO: task hung in mount_bdev (3) C 5 415d 1214d 0/1 upstream: reported C repro on 2020/12/19 04:11
linux-4.14 INFO: task hung in mount_bdev (2) 1 1482d 1482d 0/1 auto-closed as invalid on 2020/07/24 15:46
upstream INFO: task hung in mount_bdev (2) udf ext4 C done 1 1814d 1810d 0/26 closed as dup on 2019/05/03 10:52
▶ ▼ Fix bisection attempts (25)
Created Duration User Patch Repo Result
2021/11/04 07:43 12m bisect fix linux-4.19.y error job log (0)
2021/10/05 07:09 32m bisect fix linux-4.19.y job log (0) log
2021/09/05 06:37 31m bisect fix linux-4.19.y job log (0) log
2021/08/06 06:00 37m bisect fix linux-4.19.y job log (0) log
2021/07/07 05:27 31m bisect fix linux-4.19.y job log (0) log
2021/06/07 04:50 37m bisect fix linux-4.19.y job log (0) log
2021/05/08 03:29 34m bisect fix linux-4.19.y job log (0) log
2021/03/24 17:55 32m bisect fix linux-4.19.y job log (0) log
2021/02/22 17:23 32m bisect fix linux-4.19.y job log (0) log
2021/02/18 21:00 1h38m bisect fix linux-4.19.y error job log (0)
2021/02/15 01:27 0m bisect fix linux-4.19.y error job log (0)
2020/12/29 16:51 33m bisect fix linux-4.19.y job log (0) log
2020/11/29 09:36 34m bisect fix linux-4.19.y job log (0) log
2020/10/30 09:03 32m bisect fix linux-4.19.y job log (0) log
2020/09/30 05:18 35m bisect fix linux-4.19.y job log (0) log
2020/08/31 04:41 36m bisect fix linux-4.19.y job log (0) log
2020/08/01 04:05 35m bisect fix linux-4.19.y job log (0) log
2020/07/01 23:24 33m bisect fix linux-4.19.y job log (0) log
2020/06/01 22:34 35m bisect fix linux-4.19.y job log (0) log
2020/05/02 21:58 35m bisect fix linux-4.19.y job log (0) log
2020/04/02 21:24 33m bisect fix linux-4.19.y job log (0) log
2020/03/03 19:54 37m bisect fix linux-4.19.y job log (0) log
2020/02/02 19:19 35m bisect fix linux-4.19.y job log (0) log
2020/01/03 17:01 34m bisect fix linux-4.19.y job log (0) log
2019/12/04 13:46 33m bisect fix linux-4.19.y job log (0) log

Sample crash report:
UDF-fs: error (device loop1): udf_read_tagged: read failed, block=256, location=256
print_req_error: I/O error, dev loop1, sector 512
UDF-fs: error (device loop1): udf_read_tagged: read failed, block=512, location=512
INFO: task syz-executor984:8223 blocked for more than 140 seconds.
      Not tainted 4.19.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor984 D29672  8223   8137 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_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 mount_bdev+0x90/0x3b0 fs/super.c:1125
 mount_fs+0xa3/0x30c 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:2469 [inline]
 do_mount+0x113c/0x2f10 fs/namespace.c:2799
 ksys_mount+0xcf/0x130 fs/namespace.c:3015
 __do_sys_mount fs/namespace.c:3029 [inline]
 __se_sys_mount fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xba/0x150 fs/namespace.c:3026
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x44aa29
Code: Bad RIP value.
RSP: 002b:00007f92b0e28db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 000000000044aa29
RDX: 0000000020000040 RSI: 0000000020000280 RDI: 00000000200004c0
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007fff71f400ef R14: 00007f92b0e299c0 R15: 0000000000000000
INFO: task syz-executor984:8219 blocked for more than 140 seconds.
      Not tainted 4.19.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor984 D29672  8219   8140 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
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline]
 rwsem_down_write_failed+0x3aa/0x760 kernel/locking/rwsem-xadd.c:618
 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write+0x4f/0x90 kernel/locking/rwsem.c:72
 grab_super+0xa2/0x350 fs/super.c:383
 sget_userns+0x352/0xcd0 fs/super.c:511
 sget+0x102/0x140 fs/super.c:570
 mount_bdev+0xf8/0x3b0 fs/super.c:1131
 mount_fs+0xa3/0x30c 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:2469 [inline]
 do_mount+0x113c/0x2f10 fs/namespace.c:2799
 ksys_mount+0xcf/0x130 fs/namespace.c:3015
 __do_sys_mount fs/namespace.c:3029 [inline]
 __se_sys_mount fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xba/0x150 fs/namespace.c:3026
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x44aa29
Code: Bad RIP value.
RSP: 002b:00007f92b0e28db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 000000000044aa29
RDX: 0000000020000040 RSI: 0000000020000280 RDI: 00000000200004c0
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007fff71f400ef R14: 00007f92b0e299c0 R15: 0000000000000000
INFO: task syz-executor984:8222 blocked for more than 140 seconds.
      Not tainted 4.19.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor984 D29504  8222   8142 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_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 mount_bdev+0x90/0x3b0 fs/super.c:1125
 mount_fs+0xa3/0x30c 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:2469 [inline]
 do_mount+0x113c/0x2f10 fs/namespace.c:2799
 ksys_mount+0xcf/0x130 fs/namespace.c:3015
 __do_sys_mount fs/namespace.c:3029 [inline]
 __se_sys_mount fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xba/0x150 fs/namespace.c:3026
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x44aa29
Code: Bad RIP value.
RSP: 002b:00007f92b0e28db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 000000000044aa29
RDX: 0000000020000040 RSI: 0000000020000280 RDI: 00000000200004c0
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007fff71f400ef R14: 00007f92b0e299c0 R15: 0000000000000000
INFO: task syz-executor984:8224 blocked for more than 140 seconds.
      Not tainted 4.19.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor984 D29672  8224   8143 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_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 mount_bdev+0x90/0x3b0 fs/super.c:1125
 mount_fs+0xa3/0x30c 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:2469 [inline]
 do_mount+0x113c/0x2f10 fs/namespace.c:2799
 ksys_mount+0xcf/0x130 fs/namespace.c:3015
 __do_sys_mount fs/namespace.c:3029 [inline]
 __se_sys_mount fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xba/0x150 fs/namespace.c:3026
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x44aa29
Code: Bad RIP value.
RSP: 002b:00007f92b0e28db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 000000000044aa29
RDX: 0000000020000040 RSI: 0000000020000280 RDI: 00000000200004c0
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007fff71f400ef R14: 00007f92b0e299c0 R15: 0000000000000000
INFO: task syz-executor984:8247 blocked for more than 140 seconds.
      Not tainted 4.19.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor984 D29504  8247   8141 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_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072
 mount_bdev+0x90/0x3b0 fs/super.c:1125
 mount_fs+0xa3/0x30c 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:2469 [inline]
 do_mount+0x113c/0x2f10 fs/namespace.c:2799
 ksys_mount+0xcf/0x130 fs/namespace.c:3015
 __do_sys_mount fs/namespace.c:3029 [inline]
 __se_sys_mount fs/namespace.c:3026 [inline]
 __x64_sys_mount+0xba/0x150 fs/namespace.c:3026
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x44aa29
Code: Bad RIP value.
RSP: 002b:00007f92b0e28db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 000000000044aa29
RDX: 0000000020000040 RSI: 0000000020000280 RDI: 00000000200004c0
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007fff71f400ef R14: 00007f92b0e299c0 R15: 0000000000000000

Showing all locks held in the system:
1 lock held by khungtaskd/1569:
 #0: 000000009c04e342 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440
1 lock held by in:imklog/7808:
 #0: 0000000014f05fa6 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
2 locks held by syz-executor984/8220:
1 lock held by syz-executor984/8223:
 #0: 00000000886ab594 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x90/0x3b0 fs/super.c:1125
2 locks held by syz-executor984/8219:
 #0: 00000000886ab594 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x90/0x3b0 fs/super.c:1125
 #1: 00000000d837f47f (&type->s_umount_key#47){+.+.}, at: grab_super+0xa2/0x350 fs/super.c:383
1 lock held by syz-executor984/8222:
 #0: 00000000886ab594 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x90/0x3b0 fs/super.c:1125
1 lock held by syz-executor984/8224:
 #0: 00000000886ab594 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x90/0x3b0 fs/super.c:1125
1 lock held by syz-executor984/8247:
 #0: 00000000886ab594 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x90/0x3b0 fs/super.c:1125

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

NMI backtrace for cpu 1
CPU: 1 PID: 1569 Comm: khungtaskd Not tainted 4.19.167-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/0x2fe lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb 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 4.19.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x50 kernel/kcov.c:100
Code: 00 6e 88 4c 89 25 dc 57 bf 0b 41 bc f4 ff ff ff e8 00 fa ea ff 48 c7 05 c6 57 bf 0b 00 00 00 00 e9 39 ec ff ff 90 48 8b 34 24 <65> 48 8b 04 25 80 df 01 00 65 8b 15 fc 0c 9d 7e 81 e2 00 01 1f 00
RSP: 0018:ffff8880a0c6f810 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00000003aeca44c4 RCX: ffffffff81ab9c52
RDX: 00000003aeca44c4 RSI: ffffffff81ab9c60 RDI: 0000000000000006
RBP: 00000003aeca44c4 R08: 0000000000000000 R09: 00000003aeca44c4
R10: 0000000000000006 R11: 0000000000000000 R12: 0000000000000000
R13: ffffed101431ca5f R14: ffff8880a18e52f0 R15: dffffc0000000000
FS:  00007faa928758c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faa8fc62000 CR3: 00000000a0c97000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __read_once_size include/linux/compiler.h:207 [inline]
 dentry_cmp fs/dcache.c:235 [inline]
 __d_lookup_rcu+0x270/0x6b0 fs/dcache.c:2209
 lookup_fast+0x11b/0x1080 fs/namei.c:1572
 walk_component+0xde/0xda0 fs/namei.c:1807
 link_path_walk.part.0+0x901/0x1230 fs/namei.c:2142
 link_path_walk fs/namei.c:2073 [inline]
 path_openat+0x1db/0x2df0 fs/namei.c:3536
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7faa91e05840
Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24
RSP: 002b:00007ffeed1abc38 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007ffeed1abf40 RCX: 00007faa91e05840
RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 0000564bdd12c060
RBP: 000000000000000d R08: 00007faa91defc88 R09: 00000000ffffffff
R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000564bdd11f040 R14: 00007ffeed1abf00 R15: 0000564bdd12c5f0

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/01/16 01:27 linux-4.19.y 675cc038067f 65a7a854 .config console log report syz C ci2-linux-4-19
2019/08/22 05:30 linux-4.19.y a5aa80588fcd 4ea67ff8 .config console log report syz C ci2-linux-4-19
2021/04/08 03:04 linux-4.19.y b4454811f122 6a81331a .config console log report info ci2-linux-4-19 INFO: task hung in mount_bdev
* Struck through repros no longer work on HEAD.