[v6.6] INFO: task hung in xlog_grant_head_check

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 5fa4793a2d2d Linux 6.6.119
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15f5aec2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=691a6769a86ac817
dashboard link: https://syzkaller.appspot.com/bug?extid=7ece5599aa5107089a3b
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/63699875f1dd/disk-5fa4793a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8506652fcb6f/vmlinux-5fa4793a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1b30ceed1710/bzImage-5fa4793a.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7ece55...@syzkaller.appspotmail.com

INFO: task syz.3.160:6871 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.160 state:D stack:25192 pid:6871 ppid:5775 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
xlog_grant_head_wait+0x35c/0x820 fs/xfs/xfs_log.c:307
xlog_grant_head_check+0x25e/0x380 include/linux/spinlock.h:-1
xfs_log_reserve+0x348/0x970 fs/xfs/xfs_log.c:486
xfs_trans_reserve+0x225/0x690 fs/xfs/xfs_trans.c:194
xfs_trans_alloc+0x3df/0x790 fs/xfs/xfs_trans.c:283
xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190
xfs_attr_set+0x930/0x13e0 fs/xfs/libxfs/xfs_attr.c:1075
xfs_attr_change fs/xfs/xfs_xattr.c:117 [inline]
xfs_xattr_set+0x119/0x210 fs/xfs/xfs_xattr.c:162
__vfs_setxattr+0x431/0x470 fs/xattr.c:201
__vfs_setxattr_noperm+0x12d/0x5e0 fs/xattr.c:235
vfs_setxattr+0x16c/0x2f0 fs/xattr.c:322
do_setxattr fs/xattr.c:630 [inline]
path_setxattr+0x362/0x550 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:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0b6dd8f749
RSP: 002b:00007f0b6ecb2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f0b6dfe5fa0 RCX: 00007f0b6dd8f749
RDX: 0000200000000240 RSI: 0000200000000140 RDI: 0000200000000080
RBP: 00007f0b6de13f91 R08: 0000000000000002 R09: 0000000000000000
R10: 000000000000fe26 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b6dfe6038 R14: 00007f0b6dfe5fa0 R15: 00007ffdec69c298
</TASK>
INFO: task syz.3.160:6883 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.160 state:D stack:25776 pid:6883 ppid:5775 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832
rwsem_down_write_slowpath+0xbd2/0xfa0 kernel/locking/rwsem.c:1178
__down_write_common kernel/locking/rwsem.c:1306 [inline]
__down_write kernel/locking/rwsem.c:1315 [inline]
down_write+0x1a7/0x1f0 kernel/locking/rwsem.c:1574
inode_lock include/linux/fs.h:804 [inline]
process_measurement+0x3d5/0x1b00 security/integrity/ima/ima_main.c:256
ima_file_check+0xc6/0x100 security/integrity/ima/ima_main.c:568
do_open fs/namei.c:3642 [inline]
path_openat+0x2811/0x3190 fs/namei.c:3797
do_filp_open+0x1c5/0x3d0 fs/namei.c:3824
do_sys_openat2+0x12c/0x1c0 fs/open.c:1421
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1447
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0b6dd8f749
RSP: 002b:00007f0b6ec91038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0b6dfe6090 RCX: 00007f0b6dd8f749
RDX: 0000000000080441 RSI: 0000200000000040 RDI: ffffffffffffff9c
RBP: 00007f0b6de13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b6dfe6128 R14: 00007f0b6dfe6090 R15: 00007ffdec69c298
</TASK>
INFO: task syz.3.160:6900 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.160 state:D stack:27816 pid:6900 ppid:5775 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832
rwsem_down_write_slowpath+0xbd2/0xfa0 kernel/locking/rwsem.c:1178
__down_write_common kernel/locking/rwsem.c:1306 [inline]
__down_write kernel/locking/rwsem.c:1315 [inline]
down_write+0x1a7/0x1f0 kernel/locking/rwsem.c:1574
inode_lock include/linux/fs.h:804 [inline]
process_measurement+0x3d5/0x1b00 security/integrity/ima/ima_main.c:256
ima_file_check+0xc6/0x100 security/integrity/ima/ima_main.c:568
do_open fs/namei.c:3642 [inline]
path_openat+0x2811/0x3190 fs/namei.c:3797
do_filp_open+0x1c5/0x3d0 fs/namei.c:3824
do_sys_openat2+0x12c/0x1c0 fs/open.c:1421
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1447
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0b6dd8f749
RSP: 002b:00007f0b6ec70038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0b6dfe6180 RCX: 00007f0b6dd8f749
RDX: 0000000000000042 RSI: 0000200000000040 RDI: ffffffffffffff9c
RBP: 00007f0b6de13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000080 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b6dfe6218 R14: 00007f0b6dfe6180 R15: 00007ffdec69c298
</TASK>

Showing all locks held in the system:
3 locks held by kworker/u4:1/12:
#0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc90000117d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90000117d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286
1 lock held by khungtaskd/29:
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
5 locks held by kworker/u4:4/59:
#0: ffff888017873938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017873938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc900015a7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc900015a7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffffffff8dfa8610 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x136/0xb90 net/core/net_namespace.c:606
#3: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe9/0xa60 net/core/dev.c:11606
#4: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
#4: ffffffff8cd358f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x448/0x830 kernel/rcu/tree_exp.h:1004
1 lock held by dhcpcd/5432:
#0: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
#0: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6469
2 locks held by getty/5529:
#0: ffff88814de880a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000328b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
3 locks held by kworker/0:3/5840:
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc90004fbfd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc90004fbfd00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
3 locks held by syz.3.160/6871:
#0: ffff88807b452418 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff888054341a88 (&sb->s_type->i_mutex_key#30){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff888054341a88 (&sb->s_type->i_mutex_key#30){++++}-{3:3}, at: vfs_setxattr+0x145/0x2f0 fs/xattr.c:321
#2: ffff88807b452608 (sb_internal#4){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190
1 lock held by syz.3.160/6883:
#0: ffff888054341a88 (&sb->s_type->i_mutex_key#30){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#0: ffff888054341a88 (&sb->s_type->i_mutex_key#30){++++}-{3:3}, at: process_measurement+0x3d5/0x1b00 security/integrity/ima/ima_main.c:256
1 lock held by syz.3.160/6900:
#0: ffff888054341a88 (&sb->s_type->i_mutex_key#30){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#0: ffff888054341a88 (&sb->s_type->i_mutex_key#30){++++}-{3:3}, at: process_measurement+0x3d5/0x1b00 security/integrity/ima/ima_main.c:256
1 lock held by syz-executor/8576:
#0: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
#0: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6469
1 lock held by syz-executor/8587:
#0: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
#0: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6469
1 lock held by syz.7.415/8648:
#0: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline]
#0: ffffffff8dfb5448 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6469

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

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 10/25/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 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+0xf41/0xf80 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: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:148
Code: cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d 23 bb 40 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 66 0f 1f 00 55 41 57 41 56
RSP: 0018:ffffc90000187de0 EFLAGS: 000002c2
RAX: b8d5b1bb11e92e00 RBX: ffffffff8161881b RCX: b8d5b1bb11e92e00
RDX: 0000000000000001 RSI: ffffffff8aaabce0 RDI: ffffffff8afc6f80
RBP: ffffc90000187f20 R08: ffff8880b8f36b2b R09: 1ffff110171e6d65
R10: dffffc0000000000 R11: ffffed10171e6d66 R12: ffffffff8e4a2128
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff1100364e780
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000013000 CR3: 000000000cb30000 CR4: 00000000003506e0
Call Trace:
<TASK>
arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:753
default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
cpuidle_idle_call kernel/sched/idle.c:170 [inline]
do_idle+0x1eb/0x510 kernel/sched/idle.c:282
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380
start_secondary+0xee/0xf0 arch/x86/kernel/smpboot.c:323
secondary_startup_64_no_verify+0x179/0x17b
</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:
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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]

syzbot has found a reproducer for the following issue on:

HEAD commit: 5fa4793a2d2d Linux 6.6.119
git tree: linux-6.6.y

console output: https://syzkaller.appspot.com/x/log.txt?x=154caa1a580000

kernel config: https://syzkaller.appspot.com/x/.config?x=691a6769a86ac817
dashboard link: https://syzkaller.appspot.com/bug?extid=7ece5599aa5107089a3b
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=132faec2580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14329eb4580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/63699875f1dd/disk-5fa4793a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8506652fcb6f/vmlinux-5fa4793a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1b30ceed1710/bzImage-5fa4793a.xz

mounted in repro: https://storage.googleapis.com/syzbot-assets/b285d3d8f7d3/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=152faec2580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7ece55...@syzkaller.appspotmail.com

INFO: task syz.0.17:5948 blocked for more than 143 seconds.

Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

task:syz.0.17 state:D stack:24584 pid:5948 ppid:5899 flags:0x00004004

RIP: 0033:0x7f979c78f749
RSP: 002b:00007ffecdf028d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f979c9e5fa0 RCX: 00007f979c78f749

RDX: 0000200000000240 RSI: 0000200000000140 RDI: 0000200000000080

RBP: 00007f979c813f91 R08: 0000000000000002 R09: 0000000000000000

R10: 000000000000fe26 R11: 0000000000000246 R12: 0000000000000000

R13: 00007f979c9e5fa0 R14: 00007f979c9e5fa0 R15: 0000000000000005

</TASK>

Showing all locks held in the system:

1 lock held by khungtaskd/29:
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633

2 locks held by kworker/u4:2/42:
2 locks held by getty/5531:
#0: ffff88802d7c50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
3 locks held by syz.0.17/5948:
#0: ffff88802edf8418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff88805f5d1a88 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805f5d1a88 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: vfs_setxattr+0x145/0x2f0 fs/xattr.c:321
#2: ffff88802edf8608 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190
3 locks held by syz.1.18/5978:
#0: ffff88807ef8e418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff88805f5d31c8 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805f5d31c8 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: vfs_setxattr+0x145/0x2f0 fs/xattr.c:321
#2: ffff88807ef8e608 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190
3 locks held by syz.2.19/6013:
#0: ffff88807d0f8418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff88805f4da248 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805f4da248 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: vfs_setxattr+0x145/0x2f0 fs/xattr.c:321
#2: ffff88807d0f8608 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190
3 locks held by syz.3.20/6044:
#0: ffff88802eae2418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff88805f4db988 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805f4db988 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: vfs_setxattr+0x145/0x2f0 fs/xattr.c:321
#2: ffff88802eae2608 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190
3 locks held by syz.4.21/6079:
#0: ffff88805742a418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff88805f5d5888 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805f5d5888 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: vfs_setxattr+0x145/0x2f0 fs/xattr.c:321
#2: ffff88805742a608 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190
3 locks held by syz.5.22/6114:
#0: ffff888053d40418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff88805f4dd888 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805f4dd888 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: vfs_setxattr+0x145/0x2f0 fs/xattr.c:321
#2: ffff888053d40608 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190
3 locks held by syz.6.23/6155:
#0: ffff88801cbac418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff88805f5d7788 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805f5d7788 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: vfs_setxattr+0x145/0x2f0 fs/xattr.c:321
#2: ffff88801cbac608 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190
3 locks held by syz.7.24/6190:
#0: ffff888050250418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff88805f4df788 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff88805f4df788 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: vfs_setxattr+0x145/0x2f0 fs/xattr.c:321
#2: ffff888050250608 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190
3 locks held by syz.8.25/6225:
#0: ffff888050212418 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
#1: ffff888047cc1a88 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff888047cc1a88 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}, at: vfs_setxattr+0x145/0x2f0 fs/xattr.c:321
#2: ffff888050212608 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0xb1/0x340 fs/xfs/xfs_trans.c:1190

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

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 10/25/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 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+0xf41/0xf80 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: 42 Comm: kworker/u4:2 Not tainted syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025

Workqueue: bat_events batadv_nc_worker
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline]
RIP: 0010:rcu_is_watching+0x3a/0xb0 kernel/rcu/tree.c:700
Code: e8 8b f2 f7 08 89 c3 83 f8 08 73 60 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 30 8a 7c 8c 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 ac 64 6d 00 48 c7 c3 28 6b 03 00 49 03 1e 48 89
RSP: 0018:ffffc90000b2fb40 EFLAGS: 00000246
RAX: 1ffffffff18f9147 RBX: 0000000000000001 RCX: a7c08d559f8e1900
RDX: ffff88801a641e00 RSI: ffffffff8afc6f60 RDI: ffffffff8afc6f20
RBP: ffff88802c151f80 R08: dffffc0000000000 R09: 1ffffffff21b28a0
R10: dffffc0000000000 R11: fffffbfff21b28a1 R12: dffffc0000000000
R13: ffffffff8a2fc2c2 R14: ffffffff8c7c8a38 R15: dffffc0000000000

FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 000055a828726b68 CR3: 000000000cb30000 CR4: 00000000003506e0
Call Trace:
<TASK>
rcu_read_lock include/linux/rcupdate.h:787 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
batadv_nc_worker+0x10c/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792

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>

---
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