INFO: task syz.8.336:8382 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.336 state:D stack:24384 pid:8382 tgid:8381 ppid:7687 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x14fb/0x52c0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7285
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
inode_lock_nested include/linux/fs.h:1073 [inline]
__start_dirop fs/namei.c:2923 [inline]
start_dirop fs/namei.c:2934 [inline]
filename_rmdir+0x1cd/0x520 fs/namei.c:5386
__do_sys_rmdir fs/namei.c:5416 [inline]
__se_sys_rmdir+0x2e/0x140 fs/namei.c:5413
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd5ab3ec629
RSP: 002b:00007fd5a9646028 EFLAGS: 00000246 ORIG_RAX: 0000000000000054
RAX: ffffffffffffffda RBX: 00007fd5ab665fa0 RCX: 00007fd5ab3ec629
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000000c0
RBP: 00007fd5ab482b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd5ab666038 R14: 00007fd5ab665fa0 R15: 00007ffcf2345368
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcd780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
6 locks held by kworker/u8:3/57:
2 locks held by kworker/u8:4/68:
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff888019c44138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830 kernel/workqueue.c:3358
#1: ffffc9000153fc40 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc9000153fc40 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830 kernel/workqueue.c:3358
1 lock held by dhcpcd/5456:
#0: ffffffff8f1597f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f1597f8 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x32b/0x1b30 net/ipv4/devinet.c:1120
2 locks held by getty/5550:
#0: ffff8880375160a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
4 locks held by udevd/8255:
1 lock held by udevd/8354:
2 locks held by syz.8.336/8382:
#0: ffff88802b312480 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff88802a5d3430 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff88802a5d3430 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline]
#1: ffff88802a5d3430 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline]
#1: ffff88802a5d3430 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_rmdir+0x1cd/0x520 fs/namei.c:5386
6 locks held by syz.8.336/8387:
1 lock held by syz-executor/10260:
#0: ffffffff8f1597f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f1597f8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x404/0x1ad0 net/ipv4/devinet.c:978
2 locks held by syz.0.633/10295:
4 locks held by syz-executor/10329:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8387 Comm: syz.8.336 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x0/0xa0 kernel/kcov.c:299
Code: 0a 10 48 89 74 0a 18 48 89 44 0a 20 e9 09 2d 61 09 cc 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0d c8 79 89 10 65 44 8b 05 e8 79
RSP: 0018:ffffc90004a86dc0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888029d0d580 RCX: 0000000000080000
RDX: ffffc90015b1a000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000047 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000002 R12: 000000000000000a
R13: ffff888029d0d5b8 R14: 0000000000000000 R15: dffffc0000000000
FS: 00007fd5a96256c0(0000) GS:ffff888126343000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f90af4809a0 CR3: 000000002f300000 CR4: 00000000003526f0
Call Trace:
qtree_entry_unused+0x72/0xe0 fs/quota/quota_tree.c:252
v2r1_mem2diskdqb+0x31c/0x3e0 fs/quota/quota_v2.c:319
qtree_write_dquot+0x1be/0x5e0 fs/quota/quota_tree.c:460
v2_write_dquot+0x183/0x260 fs/quota/quota_v2.c:372
dquot_commit+0x377/0x450 fs/quota/dquot.c:515
ext4_write_dquot+0x20a/0x380 fs/ext4/super.c:6977
mark_dquot_dirty fs/quota/dquot.c:373 [inline]
mark_all_dquot_dirty+0x101/0x460 fs/quota/dquot.c:413
__dquot_alloc_space+0x620/0xea0 fs/quota/dquot.c:1743
dquot_alloc_space_nodirty include/linux/quotaops.h:299 [inline]
dquot_alloc_space include/linux/quotaops.h:312 [inline]
dquot_alloc_block include/linux/quotaops.h:336 [inline]
ext4_xattr_block_set+0x12b0/0x2ad0 fs/ext4/xattr.c:2058
ext4_xattr_set_handle+0xe34/0x14c0 fs/ext4/xattr.c:2457
ext4_initxattrs+0x9f/0x110 fs/ext4/xattr_security.c:44
security_inode_init_security+0x296/0x3d0 security/security.c:1344
__ext4_new_inode+0x332f/0x3d20 fs/ext4/ialloc.c:1324
ext4_create+0x233/0x470 fs/ext4/namei.c:2820
lookup_open fs/namei.c:4483 [inline]
open_last_lookups fs/namei.c:4583 [inline]
path_openat+0x13b4/0x38a0 fs/namei.c:4827
do_file_open+0x23e/0x4a0 fs/namei.c:4859
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd5ab3ec629
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd5a9625028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fd5ab666090 RCX: 00007fd5ab3ec629
RDX: 000000000000275a RSI: 0000200000000200 RDI: ffffffffffffff9c
RBP: 00007fd5ab482b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd5ab666128 R14: 00007fd5ab666090 R15: 00007ffcf2345368