* [syzbot] [bcachefs?] INFO: task hung in do_rmdir (6)
@ 2024-10-25 0:44 syzbot
2024-11-13 14:23 ` [syzbot] [kernfs?] [jfs?] " syzbot
2025-07-22 18:06 ` [syzbot] [bcachefs?] " Kent Overstreet
0 siblings, 2 replies; 3+ messages in thread
From: syzbot @ 2024-10-25 0:44 UTC (permalink / raw)
To: adilger.kernel, kent.overstreet, linux-bcachefs, linux-ext4,
linux-kernel, syzkaller-bugs, tytso
Hello,
syzbot found the following issue on:
HEAD commit: 715ca9dd687f Merge tag 'io_uring-6.12-20241019' of git://g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=163e60a7980000
kernel config: https://syzkaller.appspot.com/x/.config?x=78db40d8379956d9
dashboard link: https://syzkaller.appspot.com/bug?extid=4128a26fb0f85ec9e76c
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/bf3787869b5a/disk-715ca9dd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b938d885bc17/vmlinux-715ca9dd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9c039de0dde2/bzImage-715ca9dd.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4128a26fb0f85ec9e76c@syzkaller.appspotmail.com
INFO: task syz.4.77:6035 blocked for more than 143 seconds.
Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.77 state:D stack:25024 pid:6035 tgid:6021 ppid:5239 flags:0x00000004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5322 [inline]
__schedule+0x1843/0x4ae0 kernel/sched/core.c:6682
__schedule_loop kernel/sched/core.c:6759 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6774
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831
rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:850 [inline]
do_rmdir+0x263/0x580 fs/namei.c:4387
__do_sys_rmdir fs/namei.c:4418 [inline]
__se_sys_rmdir fs/namei.c:4416 [inline]
__x64_sys_rmdir+0x47/0x50 fs/namei.c:4416
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f271637dff9
RSP: 002b:00007f27171e6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000054
RAX: ffffffffffffffda RBX: 00007f2716536058 RCX: 00007f271637dff9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000100
RBP: 00007f27163f0296 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f2716536058 R15: 00007ffc08a709a8
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720
1 lock held by khugepaged/37:
#0: ffffffff8e9f9028 (lock#3){+.+.}-{3:3}, at: __lru_add_drain_all+0x66/0x560 mm/swap.c:843
3 locks held by kworker/u8:12/3110:
2 locks held by getty/4978:
#0: ffff88803374a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
6 locks held by syz.4.77/6025:
2 locks held by syz.4.77/6035:
#0: ffff88802b2fe420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
#1: ffff888061fdbf68 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline]
#1: ffff888061fdbf68 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4387
1 lock held by syz-executor/6680:
#0: ffffffff8e93d3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline]
#0: ffffffff8e93d3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976
2 locks held by syz-executor/7146:
2 locks held by syz.2.238/7877:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
watchdog+0xff4/0x1040 kernel/hung_task.c:379
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7146 Comm: syz-executor Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:lock_acquire+0x1e8/0x550 kernel/locking/lockdep.c:5825
Code: 02 00 00 41 0f 94 c1 48 8b 7c 24 20 44 89 f6 8b 54 24 1c 48 8b 4c 24 30 4c 8b 44 24 38 6a 00 6a 00 6a 00 ff 75 10 ff 74 24 48 <e8> c3 04 00 00 48 83 c4 28 48 c7 c7 40 dc 0a 8c e8 03 bf 4d 0a b8
RSP: 0018:ffffc900038d7698 EFLAGS: 00000006
RAX: 0000000000000001 RBX: ffffc900038d7720 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888012601bd8
RBP: ffffc900038d7808 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff2037a4e R12: 1ffff9200071aee0
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000246
FS: 00005555639f4500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe89d07e48 CR3: 000000007652c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
__raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
_raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
ext4_es_lookup_extent+0x169/0xa90 fs/ext4/extents_status.c:1015
ext4_map_blocks+0x1f9/0x1960 fs/ext4/inode.c:623
ext4_readdir+0xb25/0x3a60 fs/ext4/dir.c:182
iterate_dir+0x571/0x800 fs/readdir.c:108
__do_sys_getdents64 fs/readdir.c:407 [inline]
__se_sys_getdents64+0x1d3/0x4a0 fs/readdir.c:392
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6d7fdb0193
Code: c1 66 0f 1f 44 00 00 48 83 c4 08 48 89 ef 5b 5d e9 42 43 f8 ff 66 90 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 c7 c2 a8 ff ff ff f7 d8
RSP: 002b:00007fffae72a608 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 0000555563a17640 RCX: 00007f6d7fdb0193
RDX: 0000000000008000 RSI: 0000555563a17640 RDI: 0000000000000006
RBP: 0000555563a17614 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000293 R12: ffffffffffffffa8
R13: 0000000000000016 R14: 0000555563a17610 R15: 00007fffae72d9a0
</TASK>
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
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syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
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(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [syzbot] [kernfs?] [jfs?] INFO: task hung in do_rmdir (6)
2024-10-25 0:44 [syzbot] [bcachefs?] INFO: task hung in do_rmdir (6) syzbot
@ 2024-11-13 14:23 ` syzbot
2025-07-22 18:06 ` [syzbot] [bcachefs?] " Kent Overstreet
1 sibling, 0 replies; 3+ messages in thread
From: syzbot @ 2024-11-13 14:23 UTC (permalink / raw)
To: adilger.kernel, gregkh, jfs-discussion, kent.overstreet,
linux-bcachefs, linux-ext4, linux-kernel, shaggy, syzkaller-bugs,
tj, tytso
syzbot has found a reproducer for the following issue on:
HEAD commit: f1b785f4c787 Merge tag 'for_linus' of git://git.kernel.org..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=15c78130580000
kernel config: https://syzkaller.appspot.com/x/.config?x=1503500c6f615d24
dashboard link: https://syzkaller.appspot.com/bug?extid=4128a26fb0f85ec9e76c
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13c78130580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11f10b5f980000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0498fc027e02/disk-f1b785f4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e7fc27a5ed75/vmlinux-f1b785f4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f8db925dbfe1/bzImage-f1b785f4.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/afc6d52853ca/mount_0.gz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4128a26fb0f85ec9e76c@syzkaller.appspotmail.com
INFO: task syz-executor120:5867 blocked for more than 143 seconds.
Not tainted 6.12.0-rc7-syzkaller-00042-gf1b785f4c787 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor120 state:D stack:29104 pid:5867 tgid:5850 ppid:5846 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5328 [inline]
__schedule+0x17fa/0x4bd0 kernel/sched/core.c:6693
__schedule_loop kernel/sched/core.c:6770 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6785
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6842
rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:850 [inline]
do_rmdir+0x263/0x580 fs/namei.c:4387
__do_sys_unlinkat fs/namei.c:4575 [inline]
__se_sys_unlinkat fs/namei.c:4569 [inline]
__x64_sys_unlinkat+0xde/0xf0 fs/namei.c:4569
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ab5ccabc9
RSP: 002b:00007f5ab5c60228 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007f5ab5d5c6d8 RCX: 00007f5ab5ccabc9
RDX: 0000000000000200 RSI: 0000000020000100 RDI: 0000000000000003
RBP: 00007f5ab5d5c6d0 R08: 00007ffee618ebd7 R09: 00007f5ab5c606c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5ab5d5c6dc
R13: 00007f5ab5d1f0c0 R14: 0030656c69662f2e R15: 00007ffee618ebd8
</TASK>
INFO: task syz-executor120:5866 blocked for more than 144 seconds.
Not tainted 6.12.0-rc7-syzkaller-00042-gf1b785f4c787 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor120 state:D stack:29104 pid:5866 tgid:5851 ppid:5847 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5328 [inline]
__schedule+0x17fa/0x4bd0 kernel/sched/core.c:6693
__schedule_loop kernel/sched/core.c:6770 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6785
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6842
rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:850 [inline]
do_rmdir+0x263/0x580 fs/namei.c:4387
__do_sys_unlinkat fs/namei.c:4575 [inline]
__se_sys_unlinkat fs/namei.c:4569 [inline]
__x64_sys_unlinkat+0xde/0xf0 fs/namei.c:4569
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ab5ccabc9
RSP: 002b:00007f5ab5c60228 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007f5ab5d5c6d8 RCX: 00007f5ab5ccabc9
RDX: 0000000000000200 RSI: 0000000020000100 RDI: 0000000000000003
RBP: 00007f5ab5d5c6d0 R08: 00007ffee618ebd7 R09: 00007f5ab5c606c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5ab5d5c6dc
R13: 00007f5ab5d1f0c0 R14: 0030656c69662f2e R15: 00007ffee618ebd8
</TASK>
INFO: task syz-executor120:5864 blocked for more than 145 seconds.
Not tainted 6.12.0-rc7-syzkaller-00042-gf1b785f4c787 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor120 state:D stack:28240 pid:5864 tgid:5852 ppid:5845 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5328 [inline]
__schedule+0x17fa/0x4bd0 kernel/sched/core.c:6693
__schedule_loop kernel/sched/core.c:6770 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6785
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6842
rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:850 [inline]
do_rmdir+0x263/0x580 fs/namei.c:4387
__do_sys_unlinkat fs/namei.c:4575 [inline]
__se_sys_unlinkat fs/namei.c:4569 [inline]
__x64_sys_unlinkat+0xde/0xf0 fs/namei.c:4569
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ab5ccabc9
RSP: 002b:00007f5ab5c60228 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007f5ab5d5c6d8 RCX: 00007f5ab5ccabc9
RDX: 0000000000000200 RSI: 0000000020000100 RDI: 0000000000000003
RBP: 00007f5ab5d5c6d0 R08: 00007ffee618ebd7 R09: 00007f5ab5c606c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5ab5d5c6dc
R13: 00007f5ab5d1f0c0 R14: 0030656c69662f2e R15: 00007ffee618ebd8
</TASK>
INFO: task syz-executor120:5868 blocked for more than 145 seconds.
Not tainted 6.12.0-rc7-syzkaller-00042-gf1b785f4c787 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor120 state:D stack:29104 pid:5868 tgid:5853 ppid:5849 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5328 [inline]
__schedule+0x17fa/0x4bd0 kernel/sched/core.c:6693
__schedule_loop kernel/sched/core.c:6770 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6785
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6842
rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:850 [inline]
do_rmdir+0x263/0x580 fs/namei.c:4387
__do_sys_unlinkat fs/namei.c:4575 [inline]
__se_sys_unlinkat fs/namei.c:4569 [inline]
__x64_sys_unlinkat+0xde/0xf0 fs/namei.c:4569
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ab5ccabc9
RSP: 002b:00007f5ab5c60228 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007f5ab5d5c6d8 RCX: 00007f5ab5ccabc9
RDX: 0000000000000200 RSI: 0000000020000100 RDI: 0000000000000003
RBP: 00007f5ab5d5c6d0 R08: 00007ffee618ebd7 R09: 00007f5ab5c606c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5ab5d5c6dc
R13: 00007f5ab5d1f0c0 R14: 0030656c69662f2e R15: 00007ffee618ebd8
</TASK>
INFO: task syz-executor120:5865 blocked for more than 146 seconds.
Not tainted 6.12.0-rc7-syzkaller-00042-gf1b785f4c787 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor120 state:D stack:28088 pid:5865 tgid:5854 ppid:5848 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5328 [inline]
__schedule+0x17fa/0x4bd0 kernel/sched/core.c:6693
__schedule_loop kernel/sched/core.c:6770 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6785
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6842
rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:850 [inline]
do_rmdir+0x263/0x580 fs/namei.c:4387
__do_sys_unlinkat fs/namei.c:4575 [inline]
__se_sys_unlinkat fs/namei.c:4569 [inline]
__x64_sys_unlinkat+0xde/0xf0 fs/namei.c:4569
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ab5ccabc9
RSP: 002b:00007f5ab5c60228 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007f5ab5d5c6d8 RCX: 00007f5ab5ccabc9
RDX: 0000000000000200 RSI: 0000000020000100 RDI: 0000000000000003
RBP: 00007f5ab5d5c6d0 R08: 00007ffee618ebd7 R09: 00007f5ab5c606c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f5ab5d5c6dc
R13: 00007f5ab5d1f0c0 R14: 0030656c69662f2e R15: 00007ffee618ebd8
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720
1 lock held by kswapd0/89:
2 locks held by getty/5586:
#0: ffff88803521a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
3 locks held by syz-executor120/5859:
2 locks held by syz-executor120/5867:
#0: ffff88807b4ee420 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
#1: ffff888071e4c6c0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline]
#1: ffff888071e4c6c0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4387
2 locks held by syz-executor120/5858:
2 locks held by syz-executor120/5866:
#0: ffff88807b0e2420 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
#1: ffff888071e4c180 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline]
#1: ffff888071e4c180 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4387
4 locks held by syz-executor120/5856:
2 locks held by syz-executor120/5864:
#0: ffff8880339e2420 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
#1: ffff888071e10180 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline]
#1: ffff888071e10180 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4387
2 locks held by syz-executor120/5860:
2 locks held by syz-executor120/5868:
#0: ffff8880339ce420 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
#1: ffff888071e10c00 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline]
#1: ffff888071e10c00 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4387
2 locks held by syz-executor120/5857:
2 locks held by syz-executor120/5865:
#0: ffff88807b61a420 (sb_writers#9){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
#1: ffff888071e106c0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline]
#1: ffff888071e106c0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4387
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc7-syzkaller-00042-gf1b785f4c787 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
watchdog+0xff4/0x1040 kernel/hung_task.c:379
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5859 Comm: syz-executor120 Not tainted 6.12.0-rc7-syzkaller-00042-gf1b785f4c787 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4840 [inline]
RIP: 0010:__lock_acquire+0x724/0x2050 kernel/locking/lockdep.c:5152
Code: 84 db 40 0f b6 c5 0f b6 cb 0f 44 c8 89 4c 24 54 48 8b 44 24 38 0f b6 04 10 84 c0 0f 85 74 13 00 00 41 8b 6d 00 41 89 ec ff cd <0f> 88 a2 00 00 00 89 eb 83 fd 31 73 79 48 8d 04 9b 48 8d 5c c6 20
RSP: 0018:ffffc90004077170 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001
RDX: dffffc0000000000 RSI: ffff8880305c0ae0 RDI: 000000000000000f
RBP: 0000000000000002 R08: ffffffff94298807 R09: 1ffffffff2853100
R10: dffffc0000000000 R11: fffffbfff2853101 R12: 0000000000000003
R13: ffff8880305c0ad8 R14: 1ffff110060b816f R15: ffff8880305c0b78
FS: 00007f5ab5c816c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005611646182f8 CR3: 000000007437c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
page_ref_add_unless include/linux/page_ref.h:235 [inline]
folio_ref_add_unless include/linux/page_ref.h:248 [inline]
folio_try_get+0x3b/0x350 include/linux/page_ref.h:264
filemap_get_entry+0x240/0x3b0 mm/filemap.c:1852
__filemap_get_folio+0x71/0xbd0 mm/filemap.c:1887
__find_get_block_slow fs/buffer.c:203 [inline]
__find_get_block+0x28a/0x1150 fs/buffer.c:1404
bdev_getblk+0x33/0x550 fs/buffer.c:1431
__bread_gfp+0x86/0x400 fs/buffer.c:1491
sb_bread include/linux/buffer_head.h:346 [inline]
get_branch+0x2c3/0x6e0 fs/sysv/itree.c:102
get_block+0x180/0x16d0 fs/sysv/itree.c:222
block_read_full_folio+0x418/0xcd0 fs/buffer.c:2401
filemap_read_folio+0x14b/0x630 mm/filemap.c:2367
do_read_cache_folio+0x3f5/0x850 mm/filemap.c:3825
read_mapping_folio include/linux/pagemap.h:1011 [inline]
dir_get_folio fs/sysv/dir.c:64 [inline]
sysv_readdir+0x193/0x540 fs/sysv/dir.c:93
iterate_dir+0x571/0x800 fs/readdir.c:108
__do_sys_getdents64 fs/readdir.c:407 [inline]
__se_sys_getdents64+0x1d3/0x4a0 fs/readdir.c:392
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ab5ccabc9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5ab5c81228 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f5ab5d5c6c8 RCX: 00007f5ab5ccabc9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f5ab5d5c6c0 R08: 00007f5ab5c816c0 R09: 00007f5ab5c816c0
R10: 00007f5ab5c816c0 R11: 0000000000000246 R12: 00007f5ab5d5c6cc
R13: 00007f5ab5d1f0c0 R14: 0030656c69662f2e R15: 00007ffee618ebd8
</TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.655 msecs
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [syzbot] [bcachefs?] INFO: task hung in do_rmdir (6)
2024-10-25 0:44 [syzbot] [bcachefs?] INFO: task hung in do_rmdir (6) syzbot
2024-11-13 14:23 ` [syzbot] [kernfs?] [jfs?] " syzbot
@ 2025-07-22 18:06 ` Kent Overstreet
1 sibling, 0 replies; 3+ messages in thread
From: Kent Overstreet @ 2025-07-22 18:06 UTC (permalink / raw)
To: syzbot
Cc: adilger.kernel, linux-bcachefs, linux-ext4, linux-kernel,
syzkaller-bugs, tytso
On Thu, Oct 24, 2024 at 05:44:29PM -0700, syzbot wrote:
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 715ca9dd687f Merge tag 'io_uring-6.12-20241019' of git://g..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=163e60a7980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=78db40d8379956d9
> dashboard link: https://syzkaller.appspot.com/bug?extid=4128a26fb0f85ec9e76c
> compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
>
> Unfortunately, I don't have any reproducer for this issue yet.
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/bf3787869b5a/disk-715ca9dd.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/b938d885bc17/vmlinux-715ca9dd.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/9c039de0dde2/bzImage-715ca9dd.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+4128a26fb0f85ec9e76c@syzkaller.appspotmail.com
>
> INFO: task syz.4.77:6035 blocked for more than 143 seconds.
> Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0
> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> task:syz.4.77 state:D stack:25024 pid:6035 tgid:6021 ppid:5239 flags:0x00000004
> Call Trace:
> <TASK>
> context_switch kernel/sched/core.c:5322 [inline]
> __schedule+0x1843/0x4ae0 kernel/sched/core.c:6682
> __schedule_loop kernel/sched/core.c:6759 [inline]
> schedule+0x14b/0x320 kernel/sched/core.c:6774
> schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831
> rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
> __down_write_common kernel/locking/rwsem.c:1304 [inline]
> __down_write kernel/locking/rwsem.c:1313 [inline]
> down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694
> inode_lock_nested include/linux/fs.h:850 [inline]
> do_rmdir+0x263/0x580 fs/namei.c:4387
> __do_sys_rmdir fs/namei.c:4418 [inline]
> __se_sys_rmdir fs/namei.c:4416 [inline]
> __x64_sys_rmdir+0x47/0x50 fs/namei.c:4416
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f271637dff9
> RSP: 002b:00007f27171e6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000054
> RAX: ffffffffffffffda RBX: 00007f2716536058 RCX: 00007f271637dff9
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000100
> RBP: 00007f27163f0296 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 0000000000000000 R14: 00007f2716536058 R15: 00007ffc08a709a8
> </TASK>
>
> Showing all locks held in the system:
> 1 lock held by khungtaskd/30:
> #0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
> #0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
> #0: ffffffff8e937e20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720
> 1 lock held by khugepaged/37:
> #0: ffffffff8e9f9028 (lock#3){+.+.}-{3:3}, at: __lru_add_drain_all+0x66/0x560 mm/swap.c:843
> 3 locks held by kworker/u8:12/3110:
> 2 locks held by getty/4978:
> #0: ffff88803374a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
> #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
> 6 locks held by syz.4.77/6025:
> 2 locks held by syz.4.77/6035:
> #0: ffff88802b2fe420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
> #1: ffff888061fdbf68 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:850 [inline]
> #1: ffff888061fdbf68 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_rmdir+0x263/0x580 fs/namei.c:4387
> 1 lock held by syz-executor/6680:
> #0: ffffffff8e93d3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline]
> #0: ffffffff8e93d3b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976
> 2 locks held by syz-executor/7146:
> 2 locks held by syz.2.238/7877:
>
> =============================================
>
> NMI backtrace for cpu 0
> CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
> Call Trace:
> <TASK>
> __dump_stack lib/dump_stack.c:94 [inline]
> dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
> nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
> nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
> trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
> check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
> watchdog+0xff4/0x1040 kernel/hung_task.c:379
> kthread+0x2f0/0x390 kernel/kthread.c:389
> ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
> </TASK>
> Sending NMI from CPU 0 to CPUs 1:
> NMI backtrace for cpu 1
> CPU: 1 UID: 0 PID: 7146 Comm: syz-executor Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
> RIP: 0010:lock_acquire+0x1e8/0x550 kernel/locking/lockdep.c:5825
> Code: 02 00 00 41 0f 94 c1 48 8b 7c 24 20 44 89 f6 8b 54 24 1c 48 8b 4c 24 30 4c 8b 44 24 38 6a 00 6a 00 6a 00 ff 75 10 ff 74 24 48 <e8> c3 04 00 00 48 83 c4 28 48 c7 c7 40 dc 0a 8c e8 03 bf 4d 0a b8
> RSP: 0018:ffffc900038d7698 EFLAGS: 00000006
> RAX: 0000000000000001 RBX: ffffc900038d7720 RCX: 0000000000000001
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888012601bd8
> RBP: ffffc900038d7808 R08: 0000000000000001 R09: 0000000000000000
> R10: dffffc0000000000 R11: fffffbfff2037a4e R12: 1ffff9200071aee0
> R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000246
> FS: 00005555639f4500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007ffe89d07e48 CR3: 000000007652c000 CR4: 00000000003526f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> <NMI>
> </NMI>
> <TASK>
> __raw_read_lock include/linux/rwlock_api_smp.h:150 [inline]
> _raw_read_lock+0x36/0x50 kernel/locking/spinlock.c:228
> ext4_es_lookup_extent+0x169/0xa90 fs/ext4/extents_status.c:1015
> ext4_map_blocks+0x1f9/0x1960 fs/ext4/inode.c:623
> ext4_readdir+0xb25/0x3a60 fs/ext4/dir.c:182
> iterate_dir+0x571/0x800 fs/readdir.c:108
> __do_sys_getdents64 fs/readdir.c:407 [inline]
> __se_sys_getdents64+0x1d3/0x4a0 fs/readdir.c:392
> do_syscall_x64 arch/x86/entry/common.c:52 [inline]
> do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7f6d7fdb0193
> Code: c1 66 0f 1f 44 00 00 48 83 c4 08 48 89 ef 5b 5d e9 42 43 f8 ff 66 90 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 c7 c2 a8 ff ff ff f7 d8
> RSP: 002b:00007fffae72a608 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
> RAX: ffffffffffffffda RBX: 0000555563a17640 RCX: 00007f6d7fdb0193
> RDX: 0000000000008000 RSI: 0000555563a17640 RDI: 0000000000000006
> RBP: 0000555563a17614 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000001000 R11: 0000000000000293 R12: ffffffffffffffa8
> R13: 0000000000000016 R14: 0000555563a17610 R15: 00007fffae72d9a0
> </TASK>
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>
> If the report is already addressed, let syzbot know by replying with:
> #syz fix: exact-commit-title
>
> If you want to overwrite report's subsystems, reply with:
> #syz set subsystems: new-subsystem
> (See the list of subsystem names on the web dashboard)
>
> If the report is a duplicate of another one, reply with:
> #syz dup: exact-subject-of-another-report
>
> If you want to undo deduplication, reply with:
> #syz undup
#syz set subsystems: fs
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2025-07-22 18:06 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-10-25 0:44 [syzbot] [bcachefs?] INFO: task hung in do_rmdir (6) syzbot
2024-11-13 14:23 ` [syzbot] [kernfs?] [jfs?] " syzbot
2025-07-22 18:06 ` [syzbot] [bcachefs?] " Kent Overstreet
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