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INFO: task hung in deactivate_super (2)

Status: upstream: reported C repro on 2024/10/27 03:45
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+951b5ad6e2406186b84f@syzkaller.appspotmail.com
First crash: 40d, last: 25d
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2024/10/30 upstream (ToT) 4236f913808c C [report] INFO: task hung in deactivate_super
▶ ▼ Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 INFO: task hung in deactivate_super 3 2337d 2355d 0/3 auto-closed as invalid on 2019/02/22 12:34
linux-6.1 INFO: task hung in deactivate_super 4 475d 524d 0/3 auto-obsoleted due to no activity on 2023/11/26 12:17
linux-6.1 INFO: task hung in deactivate_super (3) 8 8d02h 192d 0/3 upstream: reported on 2024/05/27 12:00
linux-4.14 INFO: task hung in deactivate_super 1 2047d 2047d 0/1 auto-closed as invalid on 2019/10/25 08:42
upstream INFO: task hung in deactivate_super exfat 36 2158d 2261d 0/28 closed as dup on 2018/10/27 13:17
upstream INFO: task hung in deactivate_super (2) reiserfs C inconclusive done 121 278d 617d 25/28 fixed on 2024/04/08 19:23
upstream INFO: task hung in deactivate_super (3) jfs 65 5d15h 148d 0/28 upstream: reported on 2024/07/11 01:05
linux-5.15 INFO: task hung in deactivate_super 4 472d 561d 0/3 auto-obsoleted due to no activity on 2023/11/29 20:11
linux-6.1 INFO: task hung in deactivate_super (2) 1 296d 296d 0/3 auto-obsoleted due to no activity on 2024/05/24 05:27
linux-4.19 INFO: task hung in deactivate_super 4 649d 750d 0/1 upstream: reported on 2022/11/16 10:48
▶ ▼ Last patch testing requests (2)
Created Duration User Patch Repo Result
2024/11/11 03:05 14m retest repro linux-5.15.y report log
2024/11/11 03:05 14m retest repro linux-5.15.y report log

Sample crash report:
INFO: task syz-executor111:4186 blocked for more than 143 seconds.
      Not tainted 5.15.169-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor111 state:D stack:25464 pid: 4186 ppid:  4182 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 rwsem_down_write_slowpath+0xf0c/0x16a0 kernel/locking/rwsem.c:1165
 deactivate_super+0xa9/0xe0 fs/super.c:365
 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2cfddff437
RSP: 002b:00007ffc88153358 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f2cfddff437
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc88153410
RBP: 00007ffc88153410 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000202 R12: 00007ffc88154470
R13: 00005555596f16c0 R14: 0000000000000002 R15: 431bde82d7b634db
 </TASK>
INFO: task syz-executor111:4216 blocked for more than 143 seconds.
      Not tainted 5.15.169-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor111 state:D stack:26368 pid: 4216 ppid:  4187 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x9a/0x2e0 kernel/locking/rwsem.c:1500
 iterate_supers+0xac/0x1e0 fs/super.c:716
 quota_sync_all fs/quota/quota.c:68 [inline]
 __do_sys_quotactl fs/quota/quota.c:936 [inline]
 __se_sys_quotactl+0x347/0x770 fs/quota/quota.c:915
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2cfddfe1d9
RSP: 002b:00007ffc88154448 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2cfddfe1d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffc88154470
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc88154490
R13: 00007ffc881544d0 R14: 0000000000000002 R15: 431bde82d7b634db
 </TASK>
INFO: task syz-executor111:4217 blocked for more than 143 seconds.
      Not tainted 5.15.169-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor111 state:D stack:25560 pid: 4217 ppid:  4184 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x9a/0x2e0 kernel/locking/rwsem.c:1500
 iterate_supers+0xac/0x1e0 fs/super.c:716
 quota_sync_all fs/quota/quota.c:68 [inline]
 __do_sys_quotactl fs/quota/quota.c:936 [inline]
 __se_sys_quotactl+0x347/0x770 fs/quota/quota.c:915
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2cfddfe1d9
RSP: 002b:00007ffc88154448 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2cfddfe1d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffc88154470
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc88154490
R13: 00007ffc881544d0 R14: 0000000000000002 R15: 431bde82d7b634db
 </TASK>
INFO: task syz-executor111:4218 blocked for more than 144 seconds.
      Not tainted 5.15.169-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor111 state:D stack:26368 pid: 4218 ppid:  4183 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x9a/0x2e0 kernel/locking/rwsem.c:1500
 iterate_supers+0xac/0x1e0 fs/super.c:716
 quota_sync_all fs/quota/quota.c:68 [inline]
 __do_sys_quotactl fs/quota/quota.c:936 [inline]
 __se_sys_quotactl+0x347/0x770 fs/quota/quota.c:915
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2cfddfe1d9
RSP: 002b:00007ffc88154448 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2cfddfe1d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffc88154470
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc88154490
R13: 00007ffc881544d0 R14: 0000000000000002 R15: 431bde82d7b634db
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3926:
 #0: ffff88814ca96098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002ccb2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
1 lock held by syz-executor111/4186:
 #0: ffff88807c42a0e0 (&type->s_umount_key#64){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365
5 locks held by syz-executor111/4214:
1 lock held by syz-executor111/4216:
 #0: ffff88807c42a0e0 (&type->s_umount_key#64){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:716
1 lock held by syz-executor111/4217:
 #0: ffff88807c42a0e0 (&type->s_umount_key#64){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:716
1 lock held by syz-executor111/4218:
 #0: ffff88807c42a0e0 (&type->s_umount_key#64){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:716

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.169-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4214 Comm: syz-executor111 Not tainted 5.15.169-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:blk_try_enter_queue+0x0/0x4e0 block/blk-core.c:414
Code: 8c 24 e0 00 00 00 75 0f 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 fe f3 46 06 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <55> 41 57 41 56 41 55 41 54 53 48 83 ec 18 41 89 f6 49 89 fd e8 e7
RSP: 0018:ffffc90002e170d8 EFLAGS: 00000246
RAX: 1ffff11028f1290a RBX: ffff88801d2034d0 RCX: 1ffff11004b7e3ba
RDX: 1ffff11028f129fd RSI: 0000000000000000 RDI: ffff888147894740
RBP: ffffc90002e17250 R08: dffffc0000000000 R09: ffffc90002e17380
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888147894850
R13: ffff88802040a0a8 R14: ffff88802040a090 R15: dffffc0000000000
FS:  00005555596f0380(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff4f7160d8 CR3: 0000000078f4d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 bio_queue_enter block/blk-core.c:474 [inline]
 __submit_bio+0x1b4/0x850 block/blk-core.c:908
 __submit_bio_noacct_mq block/blk-core.c:997 [inline]
 submit_bio_noacct+0x955/0xb30 block/blk-core.c:1027
 submit_bio+0x2dd/0x560 block/blk-core.c:1089
 submit_bh+0x21/0x30 fs/buffer.c:3062
 flush_journal_list+0x948/0x1c80 fs/reiserfs/journal.c:1494
 flush_used_journal_lists+0x1254/0x15d0 fs/reiserfs/journal.c:1826
 do_journal_end+0x391a/0x4650
 do_journal_begin_r+0x950/0x1000
 journal_begin+0x148/0x350 fs/reiserfs/journal.c:3253
 reiserfs_sync_fs+0xac/0x140 fs/reiserfs/super.c:77
 dquot_quota_sync+0xd7/0x490 fs/quota/dquot.c:755
 iterate_supers+0x127/0x1e0 fs/super.c:718
 quota_sync_all fs/quota/quota.c:68 [inline]
 __do_sys_quotactl fs/quota/quota.c:936 [inline]
 __se_sys_quotactl+0x347/0x770 fs/quota/quota.c:915
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f2cfddfe1d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc88154448 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2cfddfe1d9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffc88154470
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc88154490
R13: 00007ffc881544d0 R14: 0000000000000002 R15: 431bde82d7b634db
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.249 msecs

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/27 13:23 linux-5.15.y 74cdd62cb470 65e8686b .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan INFO: task hung in deactivate_super
2024/10/27 03:44 linux-5.15.y 74cdd62cb470 65e8686b .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan INFO: task hung in deactivate_super
* Struck through repros no longer work on HEAD.