[v6.6] INFO: task hung in find_inode_fast (2)
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syzbot
Jul 13, 2026, 9:58:36 AM (yesterday) Jul 13
to syzkaller...@googlegroups.com
Hello,
syzbot found the following issue on:
HEAD commit: da47cbc25466 Linux 6.6.144
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=103d3346580000
kernel config: https://syzkaller.appspot.com/x/.config?x=938110aa66424b94
dashboard link: https://syzkaller.appspot.com/bug?extid=f0edb6395a6cc6b7b961
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a9e82134d7e6/disk-da47cbc2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/296a86743157/vmlinux-da47cbc2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c5adb532f254/bzImage-da47cbc2.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f0edb6...@syzkaller.appspotmail.com
INFO: task syz.1.380:7014 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.380 state:D stack:25608 pid:7014 ppid:5772 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
__wait_on_freeing_inode fs/inode.c:2317 [inline]
find_inode_fast+0x2d6/0x3f0 fs/inode.c:981
iget_locked+0xb0/0x8c0 fs/inode.c:1346
__ext4_iget+0x234/0x3f60 fs/ext4/inode.c:4846
ext4_xattr_inode_cache_find fs/ext4/xattr.c:1552 [inline]
ext4_xattr_inode_lookup_create+0x4ed/0x1ea0 fs/ext4/xattr.c:1591
ext4_xattr_block_set+0x21a/0x2fe0 fs/ext4/xattr.c:1920
ext4_xattr_set_handle+0xe95/0x1540 fs/ext4/xattr.c:2454
ext4_xattr_set+0x254/0x340 fs/ext4/xattr.c:2556
__vfs_setxattr+0x437/0x470 fs/xattr.c:201
__vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:235
vfs_setxattr+0x16b/0x2f0 fs/xattr.c:322
do_setxattr fs/xattr.c:630 [inline]
path_setxattr+0x33a/0x590 fs/xattr.c:659
__do_sys_setxattr fs/xattr.c:677 [inline]
__se_sys_setxattr fs/xattr.c:673 [inline]
__x64_sys_setxattr+0xbb/0xd0 fs/xattr.c:673
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f161c39de59
RSP: 002b:00007f161d312028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f161c626090 RCX: 00007f161c39de59
RDX: 0000200000001400 RSI: 00002000000001c0 RDI: 0000200000000380
RBP: 00007f161c433e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000835 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f161c626128 R14: 00007f161c626090 R15: 00007ffee5fcf1a8
</TASK>
INFO: task syz.1.380:7017 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.380 state:D stack:25768 pid:7017 ppid:5772 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
mb_cache_entry_wait_unused+0x17e/0x270 fs/mbcache.c:148
ext4_evict_ea_inode+0x14d/0x2f0 fs/ext4/xattr.c:481
ext4_evict_inode+0x153/0xe70 fs/ext4/inode.c:183
evict+0x4b7/0x8a0 fs/inode.c:705
ext4_xattr_set_entry+0x1758/0x1ee0 fs/ext4/xattr.c:1851
ext4_xattr_block_set+0x661/0x2fe0 fs/ext4/xattr.c:1963
ext4_xattr_set_handle+0xe95/0x1540 fs/ext4/xattr.c:2454
ext4_xattr_set+0x254/0x340 fs/ext4/xattr.c:2556
__vfs_setxattr+0x437/0x470 fs/xattr.c:201
__vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:235
vfs_setxattr+0x16b/0x2f0 fs/xattr.c:322
do_setxattr fs/xattr.c:630 [inline]
path_setxattr+0x33a/0x590 fs/xattr.c:659
__do_sys_setxattr fs/xattr.c:677 [inline]
__se_sys_setxattr fs/xattr.c:673 [inline]
__x64_sys_setxattr+0xbb/0xd0 fs/xattr.c:673
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f161c39de59
RSP: 002b:00007f161d2f1028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f161c626180 RCX: 00007f161c39de59
RDX: 0000200000000000 RSI: 00002000000001c0 RDI: 0000200000000040
RBP: 00007f161c433e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000835 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f161c626218 R14: 00007f161c626180 R15: 00007ffee5fcf1a8
</TASK>
Showing all locks held in the system:
2 locks held by kworker/1:0/23:
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc900001d7d00 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc900001d7d00 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
1 lock held by khungtaskd/29:
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
3 locks held by kworker/u4:7/2955:
3 locks held by kworker/u4:8/3465:
#0: ffff88801d243138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff88801d243138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc9000ca47d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000ca47d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#2: ffff888019e560e0 (&type->s_umount_key#43){.+.+}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607
2 locks held by kworker/u4:10/4462:
#0: ffff8880b8f3c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
#1: ffffc9000e917d00 ((reaper_work).work){+.+.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffffc9000e917d00 ((reaper_work).work){+.+.}-{0:0}, at: __schedule+0x21d3/0x4660 kernel/sched/core.c:6695
2 locks held by getty/5528:
#0: ffff8880314620a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
1 lock held by udevd/5777:
3 locks held by syz.1.380/7014:
#0: ffff88805a79a418 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff88805ed7ac10 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805ed7ac10 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:321
#2: ffff88805ed7a8c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline]
#2: ffff88805ed7a8c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x195/0x1540 fs/ext4/xattr.c:2369
3 locks held by syz.1.380/7017:
#0: ffff88805a79a418 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff8880785de810 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff8880785de810 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:321
#2: ffff8880785de4c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline]
#2: ffff8880785de4c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x195/0x1540 fs/ext4/xattr.c:2369
1 lock held by syz-executor/7333:
#0: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#0: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
1 lock held by syz.3.826/8269:
#0: ffff888140bb24c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1a4/0x320 block/bdev.c:1076
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
<TASK>
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf59/0xfa0 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7333 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:lock_accessed kernel/locking/lockdep.c:1525 [inline]
RIP: 0010:__bfs kernel/locking/lockdep.c:1749 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1844 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2804 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3138 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3253 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3869 [inline]
RIP: 0010:__lock_acquire+0x3dd2/0x7d80 kernel/locking/lockdep.c:5137
Code: 94 17 77 00 48 ba 00 00 00 00 00 fc ff df 4c 8b 3b 4d 85 ff 0f 84 59 2a 00 00 49 83 c7 5c 4d 89 fc 49 c1 ec 03 41 0f b6 04 14 <84> c0 0f 85 77 03 00 00 8b 1d 30 75 bb 11 41 39 1f 0f 84 a5 fe ff
RSP: 0018:ffffc9000bbc6f40 EFLAGS: 00000803
RAX: 0000000000000000 RBX: ffffffff93d0c8e8 RCX: 00000000000004ee
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff90b5a6e0
RBP: ffffc9000bbc7188 R08: ffffc9000bbc7117 R09: 0000000000000000
R10: ffffc9000bbc70e0 R11: fffff52001778e23 R12: 1ffffffff2177279
R13: 1ffffffff27a191d R14: ffffffff93d0c8d8 R15: ffffffff90bb93cc
FS: 000055555cad4500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555caefa38 CR3: 000000004a2f2000 CR4: 00000000003506e0
Call Trace:
<TASK>
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xb4/0x100 kernel/locking/spinlock.c:162
debug_object_activate+0x6c/0x500 lib/debugobjects.c:747
debug_timer_activate kernel/time/timer.c:782 [inline]
__mod_timer+0x8d2/0xd60 kernel/time/timer.c:1119
schedule_timeout+0x183/0x2d0 kernel/time/timer.c:2167
io_schedule_timeout+0x89/0xe0 kernel/sched/core.c:9011
f2fs_wait_on_all_pages+0x1c8/0x420 fs/f2fs/checkpoint.c:1319
do_checkpoint+0x2161/0x3b30 fs/f2fs/checkpoint.c:1564
f2fs_write_checkpoint+0x177a/0x1f70 fs/f2fs/checkpoint.c:1686
f2fs_put_super+0x5f8/0x1480 fs/f2fs/super.c:1621
generic_shutdown_super+0x134/0x2b0 fs/super.c:693
kill_block_super+0x44/0x90 fs/super.c:1660
kill_f2fs_super+0x32d/0x3f0 fs/f2fs/super.c:4899
deactivate_locked_super+0x97/0x100 fs/super.c:481
cleanup_mnt+0x3d7/0x460 fs/namespace.c:1259
task_work_run+0x1d4/0x260 kernel/task_work.c:245
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd49859f097
Code: a2 c7 05 5c 26 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc2eca6c88 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fd4986332ca RCX: 00007fd49859f097
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc2eca6d40
RBP: 00007ffc2eca6d40 R08: 00007ffc2eca7d40 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc2eca7dd0
R13: 00007fd4986332ca R14: 000000000004bceb R15: 00007ffc2eca7e10
</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 syzk...@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
syzbot found the following issue on:
HEAD commit: da47cbc25466 Linux 6.6.144
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=103d3346580000
kernel config: https://syzkaller.appspot.com/x/.config?x=938110aa66424b94
dashboard link: https://syzkaller.appspot.com/bug?extid=f0edb6395a6cc6b7b961
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a9e82134d7e6/disk-da47cbc2.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/296a86743157/vmlinux-da47cbc2.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c5adb532f254/bzImage-da47cbc2.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f0edb6...@syzkaller.appspotmail.com
INFO: task syz.1.380:7014 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.380 state:D stack:25608 pid:7014 ppid:5772 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
__wait_on_freeing_inode fs/inode.c:2317 [inline]
find_inode_fast+0x2d6/0x3f0 fs/inode.c:981
iget_locked+0xb0/0x8c0 fs/inode.c:1346
__ext4_iget+0x234/0x3f60 fs/ext4/inode.c:4846
ext4_xattr_inode_cache_find fs/ext4/xattr.c:1552 [inline]
ext4_xattr_inode_lookup_create+0x4ed/0x1ea0 fs/ext4/xattr.c:1591
ext4_xattr_block_set+0x21a/0x2fe0 fs/ext4/xattr.c:1920
ext4_xattr_set_handle+0xe95/0x1540 fs/ext4/xattr.c:2454
ext4_xattr_set+0x254/0x340 fs/ext4/xattr.c:2556
__vfs_setxattr+0x437/0x470 fs/xattr.c:201
__vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:235
vfs_setxattr+0x16b/0x2f0 fs/xattr.c:322
do_setxattr fs/xattr.c:630 [inline]
path_setxattr+0x33a/0x590 fs/xattr.c:659
__do_sys_setxattr fs/xattr.c:677 [inline]
__se_sys_setxattr fs/xattr.c:673 [inline]
__x64_sys_setxattr+0xbb/0xd0 fs/xattr.c:673
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f161c39de59
RSP: 002b:00007f161d312028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f161c626090 RCX: 00007f161c39de59
RDX: 0000200000001400 RSI: 00002000000001c0 RDI: 0000200000000380
RBP: 00007f161c433e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000835 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f161c626128 R14: 00007f161c626090 R15: 00007ffee5fcf1a8
</TASK>
INFO: task syz.1.380:7017 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.380 state:D stack:25768 pid:7017 ppid:5772 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6700
schedule+0xbd/0x170 kernel/sched/core.c:6774
mb_cache_entry_wait_unused+0x17e/0x270 fs/mbcache.c:148
ext4_evict_ea_inode+0x14d/0x2f0 fs/ext4/xattr.c:481
ext4_evict_inode+0x153/0xe70 fs/ext4/inode.c:183
evict+0x4b7/0x8a0 fs/inode.c:705
ext4_xattr_set_entry+0x1758/0x1ee0 fs/ext4/xattr.c:1851
ext4_xattr_block_set+0x661/0x2fe0 fs/ext4/xattr.c:1963
ext4_xattr_set_handle+0xe95/0x1540 fs/ext4/xattr.c:2454
ext4_xattr_set+0x254/0x340 fs/ext4/xattr.c:2556
__vfs_setxattr+0x437/0x470 fs/xattr.c:201
__vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:235
vfs_setxattr+0x16b/0x2f0 fs/xattr.c:322
do_setxattr fs/xattr.c:630 [inline]
path_setxattr+0x33a/0x590 fs/xattr.c:659
__do_sys_setxattr fs/xattr.c:677 [inline]
__se_sys_setxattr fs/xattr.c:673 [inline]
__x64_sys_setxattr+0xbb/0xd0 fs/xattr.c:673
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f161c39de59
RSP: 002b:00007f161d2f1028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f161c626180 RCX: 00007f161c39de59
RDX: 0000200000000000 RSI: 00002000000001c0 RDI: 0000200000000040
RBP: 00007f161c433e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000835 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f161c626218 R14: 00007f161c626180 R15: 00007ffee5fcf1a8
</TASK>
Showing all locks held in the system:
2 locks held by kworker/1:0/23:
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc900001d7d00 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc900001d7d00 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
1 lock held by khungtaskd/29:
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
3 locks held by kworker/u4:7/2955:
3 locks held by kworker/u4:8/3465:
#0: ffff88801d243138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#0: ffff88801d243138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#1: ffffc9000ca47d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2628 [inline]
#1: ffffc9000ca47d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2730
#2: ffff888019e560e0 (&type->s_umount_key#43){.+.+}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607
2 locks held by kworker/u4:10/4462:
#0: ffff8880b8f3c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
#1: ffffc9000e917d00 ((reaper_work).work){+.+.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffffc9000e917d00 ((reaper_work).work){+.+.}-{0:0}, at: __schedule+0x21d3/0x4660 kernel/sched/core.c:6695
2 locks held by getty/5528:
#0: ffff8880314620a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
1 lock held by udevd/5777:
3 locks held by syz.1.380/7014:
#0: ffff88805a79a418 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff88805ed7ac10 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805ed7ac10 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:321
#2: ffff88805ed7a8c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline]
#2: ffff88805ed7a8c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x195/0x1540 fs/ext4/xattr.c:2369
3 locks held by syz.1.380/7017:
#0: ffff88805a79a418 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff8880785de810 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff8880785de810 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:321
#2: ffff8880785de4c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline]
#2: ffff8880785de4c8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x195/0x1540 fs/ext4/xattr.c:2369
1 lock held by syz-executor/7333:
#0: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#0: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
1 lock held by syz.3.826/8269:
#0: ffff888140bb24c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1a4/0x320 block/bdev.c:1076
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
<TASK>
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf59/0xfa0 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7333 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:lock_accessed kernel/locking/lockdep.c:1525 [inline]
RIP: 0010:__bfs kernel/locking/lockdep.c:1749 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1844 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2804 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3138 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3253 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3869 [inline]
RIP: 0010:__lock_acquire+0x3dd2/0x7d80 kernel/locking/lockdep.c:5137
Code: 94 17 77 00 48 ba 00 00 00 00 00 fc ff df 4c 8b 3b 4d 85 ff 0f 84 59 2a 00 00 49 83 c7 5c 4d 89 fc 49 c1 ec 03 41 0f b6 04 14 <84> c0 0f 85 77 03 00 00 8b 1d 30 75 bb 11 41 39 1f 0f 84 a5 fe ff
RSP: 0018:ffffc9000bbc6f40 EFLAGS: 00000803
RAX: 0000000000000000 RBX: ffffffff93d0c8e8 RCX: 00000000000004ee
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffffffff90b5a6e0
RBP: ffffc9000bbc7188 R08: ffffc9000bbc7117 R09: 0000000000000000
R10: ffffc9000bbc70e0 R11: fffff52001778e23 R12: 1ffffffff2177279
R13: 1ffffffff27a191d R14: ffffffff93d0c8d8 R15: ffffffff90bb93cc
FS: 000055555cad4500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555caefa38 CR3: 000000004a2f2000 CR4: 00000000003506e0
Call Trace:
<TASK>
lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xb4/0x100 kernel/locking/spinlock.c:162
debug_object_activate+0x6c/0x500 lib/debugobjects.c:747
debug_timer_activate kernel/time/timer.c:782 [inline]
__mod_timer+0x8d2/0xd60 kernel/time/timer.c:1119
schedule_timeout+0x183/0x2d0 kernel/time/timer.c:2167
io_schedule_timeout+0x89/0xe0 kernel/sched/core.c:9011
f2fs_wait_on_all_pages+0x1c8/0x420 fs/f2fs/checkpoint.c:1319
do_checkpoint+0x2161/0x3b30 fs/f2fs/checkpoint.c:1564
f2fs_write_checkpoint+0x177a/0x1f70 fs/f2fs/checkpoint.c:1686
f2fs_put_super+0x5f8/0x1480 fs/f2fs/super.c:1621
generic_shutdown_super+0x134/0x2b0 fs/super.c:693
kill_block_super+0x44/0x90 fs/super.c:1660
kill_f2fs_super+0x32d/0x3f0 fs/f2fs/super.c:4899
deactivate_locked_super+0x97/0x100 fs/super.c:481
cleanup_mnt+0x3d7/0x460 fs/namespace.c:1259
task_work_run+0x1d4/0x260 kernel/task_work.c:245
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd49859f097
Code: a2 c7 05 5c 26 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc2eca6c88 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fd4986332ca RCX: 00007fd49859f097
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc2eca6d40
RBP: 00007ffc2eca6d40 R08: 00007ffc2eca7d40 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc2eca7dd0
R13: 00007fd4986332ca R14: 000000000004bceb R15: 00007ffc2eca7e10
</TASK>
---
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