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INFO: task hung in mount_bdev (2)

Status: closed as dup on 2019/05/03 10:52
Subsystems: udf ext4
[Documentation on labels]
Reported-by: syzbot+97889fb583ef1f3d42c6@syzkaller.appspotmail.com
First crash: 2034d, last: 2034d
Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: no output from test machine (log)
Repro: C syz .config
  
▶ ▼ Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
INFO: task hung in __get_super fs C 80 1982d 2426d
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
INFO: task hung in mount_bdev (2) 0 (1) 2019/05/03 01:06
▶ ▼ 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 1839d 1839d 0/1 auto-closed as invalid on 2020/03/08 13:23
upstream INFO: task hung in mount_bdev isofs 1 2170d 2169d 0/28 closed as dup on 2018/12/14 15:35
linux-4.14 INFO: task hung in mount_bdev (3) C 5 635d 1434d 0/1 upstream: reported C repro on 2020/12/19 04:11
linux-4.14 INFO: task hung in mount_bdev (2) 1 1701d 1701d 0/1 auto-closed as invalid on 2020/07/24 15:46
linux-4.19 INFO: task hung in mount_bdev C error 3 1144d 1919d 0/1 upstream: reported C repro on 2019/08/22 06:31

Sample crash report:
INFO: task syz-executor013:7561 blocked for more than 143 seconds.
      Not tainted 5.1.0-rc6+ #90
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor013 D29336  7561   7543 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 mount_bdev+0x93/0x3c0 fs/super.c:1313
 udf_mount+0x35/0x40 fs/udf/super.c:131
 legacy_get_tree+0xf2/0x200 fs/fs_context.c:584
 vfs_get_tree+0x123/0x450 fs/super.c:1481
 do_new_mount fs/namespace.c:2622 [inline]
 do_mount+0x1436/0x2c40 fs/namespace.c:2942
 ksys_mount+0xdb/0x150 fs/namespace.c:3151
 __do_sys_mount fs/namespace.c:3165 [inline]
 __se_sys_mount fs/namespace.c:3162 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3162
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x44a739
Code: 00 49 6e 76 61 6c 69 64 20 22 24 41 63 74 69 6f 6e 51 75 65 75 65 43 68 65 63 6b 70 6f 69 6e 74 49 6e 74 65 72 76 61 6c 22 2c <20> 65 72 72 6f 72 20 25 64 2e 20 49 67 6e 6f 72 65 64 2c 20 72 75
RSP: 002b:00007f9541ef0db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 000000000044a739
RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000020000080
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffc6cf3cddf R14: 00007f9541ef19c0 R15: 0000000000000000
INFO: task syz-executor013:7563 blocked for more than 143 seconds.
      Not tainted 5.1.0-rc6+ #90
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor013 D29720  7563   7541 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 mount_bdev+0x93/0x3c0 fs/super.c:1313
 udf_mount+0x35/0x40 fs/udf/super.c:131
 legacy_get_tree+0xf2/0x200 fs/fs_context.c:584
 vfs_get_tree+0x123/0x450 fs/super.c:1481
 do_new_mount fs/namespace.c:2622 [inline]
 do_mount+0x1436/0x2c40 fs/namespace.c:2942
 ksys_mount+0xdb/0x150 fs/namespace.c:3151
 __do_sys_mount fs/namespace.c:3165 [inline]
 __se_sys_mount fs/namespace.c:3162 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3162
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x44a739
Code: 00 49 6e 76 61 6c 69 64 20 22 24 41 63 74 69 6f 6e 51 75 65 75 65 43 68 65 63 6b 70 6f 69 6e 74 49 6e 74 65 72 76 61 6c 22 2c <20> 65 72 72 6f 72 20 25 64 2e 20 49 67 6e 6f 72 65 64 2c 20 72 75
RSP: 002b:00007f9541ef0db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 000000000044a739
RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000020000080
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffc6cf3cddf R14: 00007f9541ef19c0 R15: 0000000000000000
INFO: task syz-executor013:7559 blocked for more than 143 seconds.
      Not tainted 5.1.0-rc6+ #90
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor013 D29096  7559   7544 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:582 [inline]
 rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:611
 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write+0x53/0x90 kernel/locking/rwsem.c:72
 grab_super+0xb4/0x290 fs/super.c:385
 sget_userns+0x1ab/0x560 fs/super.c:601
 sget+0x10c/0x150 fs/super.c:660
 mount_bdev+0xff/0x3c0 fs/super.c:1319
 udf_mount+0x35/0x40 fs/udf/super.c:131
 legacy_get_tree+0xf2/0x200 fs/fs_context.c:584
 vfs_get_tree+0x123/0x450 fs/super.c:1481
 do_new_mount fs/namespace.c:2622 [inline]
 do_mount+0x1436/0x2c40 fs/namespace.c:2942
 ksys_mount+0xdb/0x150 fs/namespace.c:3151
 __do_sys_mount fs/namespace.c:3165 [inline]
 __se_sys_mount fs/namespace.c:3162 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3162
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x44a739
Code: 00 49 6e 76 61 6c 69 64 20 22 24 41 63 74 69 6f 6e 51 75 65 75 65 43 68 65 63 6b 70 6f 69 6e 74 49 6e 74 65 72 76 61 6c 22 2c <20> 65 72 72 6f 72 20 25 64 2e 20 49 67 6e 6f 72 65 64 2c 20 72 75
RSP: 002b:00007f9541ef0db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 000000000044a739
RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000020000080
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffc6cf3cddf R14: 00007f9541ef19c0 R15: 0000000000000000
INFO: task syz-executor013:7565 blocked for more than 144 seconds.
      Not tainted 5.1.0-rc6+ #90
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor013 D29720  7565   7542 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 mount_bdev+0x93/0x3c0 fs/super.c:1313
 udf_mount+0x35/0x40 fs/udf/super.c:131
 legacy_get_tree+0xf2/0x200 fs/fs_context.c:584
 vfs_get_tree+0x123/0x450 fs/super.c:1481
 do_new_mount fs/namespace.c:2622 [inline]
 do_mount+0x1436/0x2c40 fs/namespace.c:2942
 ksys_mount+0xdb/0x150 fs/namespace.c:3151
 __do_sys_mount fs/namespace.c:3165 [inline]
 __se_sys_mount fs/namespace.c:3162 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3162
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x44a739
Code: 00 49 6e 76 61 6c 69 64 20 22 24 41 63 74 69 6f 6e 51 75 65 75 65 43 68 65 63 6b 70 6f 69 6e 74 49 6e 74 65 72 76 61 6c 22 2c <20> 65 72 72 6f 72 20 25 64 2e 20 49 67 6e 6f 72 65 64 2c 20 72 75
RSP: 002b:00007f9541ef0db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 000000000044a739
RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000020000080
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffc6cf3cddf R14: 00007f9541ef19c0 R15: 0000000000000000
INFO: task syz-executor013:7562 blocked for more than 144 seconds.
      Not tainted 5.1.0-rc6+ #90
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor013 D29720  7562   7546 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x813/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 mount_bdev+0x93/0x3c0 fs/super.c:1313
 udf_mount+0x35/0x40 fs/udf/super.c:131
 legacy_get_tree+0xf2/0x200 fs/fs_context.c:584
 vfs_get_tree+0x123/0x450 fs/super.c:1481
 do_new_mount fs/namespace.c:2622 [inline]
 do_mount+0x1436/0x2c40 fs/namespace.c:2942
 ksys_mount+0xdb/0x150 fs/namespace.c:3151
 __do_sys_mount fs/namespace.c:3165 [inline]
 __se_sys_mount fs/namespace.c:3162 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3162
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x44a739
Code: 00 49 6e 76 61 6c 69 64 20 22 24 41 63 74 69 6f 6e 51 75 65 75 65 43 68 65 63 6b 70 6f 69 6e 74 49 6e 74 65 72 76 61 6c 22 2c <20> 65 72 72 6f 72 20 25 64 2e 20 49 67 6e 6f 72 65 64 2c 20 72 75
RSP: 002b:00007f9541ef0db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 000000000044a739
RDX: 0000000020000240 RSI: 0000000020000200 RDI: 0000000020000080
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffc6cf3cddf R14: 00007f9541ef19c0 R15: 0000000000000000

Showing all locks held in the system:
1 lock held by khungtaskd/1042:
 #0: 000000006329251d (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5057
1 lock held by rsyslogd/7425:
 #0: 00000000d77ddd95 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801
2 locks held by getty/7515:
 #0: 000000004c45b4e6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000cb1f5c30 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7516:
 #0: 0000000061e5eac7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000aab03c35 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7517:
 #0: 00000000205ee5b4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 0000000002712bdb (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7518:
 #0: 000000000cc046b2 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000d5140a4a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7519:
 #0: 000000003624da6d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000f5b16893 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7520:
 #0: 0000000082294f91 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000870dfcb5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7521:
 #0: 000000000f72fa86 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000a044b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by syz-executor013/7547:
1 lock held by syz-executor013/7561:
 #0: 00000000d97cb347 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x93/0x3c0 fs/super.c:1313
1 lock held by syz-executor013/7563:
 #0: 00000000d97cb347 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x93/0x3c0 fs/super.c:1313
2 locks held by syz-executor013/7559:
 #0: 00000000d97cb347 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x93/0x3c0 fs/super.c:1313
 #1: 000000001ecfe564 (&type->s_umount_key#39){+.+.}, at: grab_super+0xb4/0x290 fs/super.c:385
1 lock held by syz-executor013/7565:
 #0: 00000000d97cb347 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x93/0x3c0 fs/super.c:1313
1 lock held by syz-executor013/7562:
 #0: 00000000d97cb347 (&bdev->bd_fsfreeze_mutex){+.+.}, at: mount_bdev+0x93/0x3c0 fs/super.c:1313

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

NMI backtrace for cpu 1
CPU: 1 PID: 1042 Comm: khungtaskd Not tainted 5.1.0-rc6+ #90
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+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline]
 watchdog+0x9b7/0xec0 kernel/hung_task.c:288
 kthread+0x357/0x430 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 1 to CPUs 0:

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/04/29 00:04 upstream 9520b5324b0e b617407b .config console log report syz C ci-upstream-kasan-gce-root
* Struck through repros no longer work on HEAD.