INFO: tas[ 305.832337][ T38] INFO: task syz.0.110:6435 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.110 state:D stack:25560 pid:6435 tgid:6418 ppid:5600 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7607
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1670 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
__rt_mutex_slowlock_locked+0x1f84/0x25b0 kernel/locking/rtmutex.c:1787
rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1827
__rt_mutex_lock kernel/locking/rtmutex.c:1842 [inline]
rwbase_write_lock+0x14c/0x720 kernel/locking/rwbase_rt.c:251
inode_lock include/linux/fs.h:1024 [inline]
__blockdev_direct_IO+0x358/0x33d0 fs/direct-io.c:1136
blockdev_direct_IO include/linux/fs.h:3130 [inline]
fat_direct_IO+0x1be/0x2f0 fs/fat/inode.c:284
generic_file_read_iter+0x346/0x560 mm/filemap.c:2983
new_sync_read fs/read_write.c:493 [inline]
vfs_read+0x59e/0xa90 fs/read_write.c:574
ksys_read+0x156/0x270 fs/read_write.c:716
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7cd55bce59
RSP: 002b:00007f7cd37ed028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f7cd5836090 RCX: 00007f7cd55bce59
RDX: 0000000000002020 RSI: 0000200000005300 RDI: 0000000000000004
RBP: 00007f7cd5652e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7cd5836128 R14: 00007f7cd5836090 R15: 00007ffc32114cb8
Showing all locks held in the system:
5 locks held by kworker/u8:1/14:
1 lock held by khungtaskd/38:
#0: ffffffff8dfc2fc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8dfc2fc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8dfc2fc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5356:
#0: ffff888029a350a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
3 locks held by syz-executor/5599:
4 locks held by syz-executor/5603:
5 locks held by udevd/5722:
1 lock held by udevd/5926:
#0: ffff8880229a6608 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1039 [inline]
#0: ffff8880229a6608 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_read_iter+0x2e6/0x430 block/fops.c:829
3 locks held by syz.0.110/6422:
2 locks held by syz.0.110/6435:
#0: ffff888029d75528 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1259
#1: ffff88804035e430 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
#1: ffff88804035e430 (&sb->s_type->i_mutex_key#33){++++}-{4:4}, at: __blockdev_direct_IO+0x358/0x33d0 fs/direct-io.c:1136
8 locks held by syz.6.384/7884:
2 locks held by syz.6.384/7899:
#0: ffff88803a304500 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
#1: ffff88806071d2f8 (&type->i_mutex_dir_key#19/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1069 [inline]
#1: ffff88806071d2f8 (&type->i_mutex_dir_key#19/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline]
#1: ffff88806071d2f8 (&type->i_mutex_dir_key#19/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline]
#1: ffff88806071d2f8 (&type->i_mutex_dir_key#19/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4951
4 locks held by syz.2.387/7890:
3 locks held by syz.5.388/7896:
=============================================
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 05/09/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 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: 5599 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:__bfs kernel/locking/lockdep.c:1815 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x18fa/0x2ce0 kernel/locking/lockdep.c:5237
Code: 13 25 ff 0f 00 00 39 05 b0 d6 d7 11 73 06 89 05 a8 d6 d7 11 48 8b 02 48 89 df 4c 39 e8 0f 84 34 fe ff ff 4c 89 78 30 48 8b 00 <4c> 39 e8 75 f4 48 89 df e9 20 fe ff ff 48 89 fb 48 c7 c7 b0 02 e9
RSP: 0018:ffffc900043ff618 EFLAGS: 00000002
RAX: ffffffff96234578 RBX: 0000000000000101 RCX: 0000000000000002
RDX: ffffffff95fd2078 RSI: ffff888030bc2bd0 RDI: 0000000000000101
RBP: 74e67a4e533e33e7 R08: ffffc900043ff5e0 R09: 0000000000000020
R10: 0000000000000000 R11: ffffffff81a124a0 R12: 0000000000000001
R13: ffffffff931a9348 R14: ffff888030bc1f00 R15: ffffc900043ff6a8
FS: 000055556714d500(0000) GS:ffff888126111000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd848963000 CR3: 000000005a8fc000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
debug_object_deactivate+0x9a/0x250 lib/debugobjects.c:936
debug_hrtimer_deactivate kernel/time/hrtimer.c:490 [inline]
remove_and_enqueue_same_base kernel/time/hrtimer.c:1252 [inline]
__hrtimer_start_range_ns kernel/time/hrtimer.c:1402 [inline]
hrtimer_start_range_ns_common+0x3ee/0xb90 kernel/time/hrtimer.c:1481
hrtimer_start_range_ns+0x111/0x3f0 kernel/time/hrtimer.c:1503
hrtimer_start include/linux/hrtimer.h:223 [inline]
hrtick_cond_restart kernel/sched/core.c:939 [inline]
hrtick_schedule_exit kernel/sched/core.c:1001 [inline]
finish_lock_switch kernel/sched/core.c:5240 [inline]
finish_task_switch+0x3c4/0xc60 kernel/sched/core.c:5359
context_switch kernel/sched/core.c:5513 [inline]
__schedule+0x16e4/0x5500 kernel/sched/core.c:7234
preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7413
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:179 [inline]
_raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:198
rcu_report_unblock_qs_rnp kernel/rcu/tree.c:2454 [inline]
rcu_preempt_deferred_qs_irqrestore+0x911/0xb90 kernel/rcu/tree_plugin.h:571
__rcu_read_unlock+0x83/0xe0 kernel/rcu/tree_plugin.h:438
generic_update_time fs/inode.c:2257 [inline]
touch_atime+0x565/0x670 fs/inode.c:2332
file_accessed include/linux/fs.h:2272 [inline]
iterate_dir+0x37d/0x4e0 fs/readdir.c:113
__do_sys_getdents64 fs/readdir.c:399 [inline]
__se_sys_getdents64+0xf1/0x280 fs/readdir.c:384
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe0e05d57f3
Code: c7 c0 e8 ff ff ff 64 c7 00 16 00 00 00 31 c0 eb 9e e8 81 9b fd ff 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 e8 ff ff ff f7 d8
RSP: 002b:00007fff0997e968 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 0000555567168a30 RCX: 00007fe0e05d57f3
RDX: 0000000000008000 RSI: 0000555567168a60 RDI: 0000000000000005
RBP: 0000555567168a60 R08: 00007fe0e07fde20 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000293 R12: 0000555567168a34
R13: ffffffffffffffe8 R14: 0000000000000016 R15: 00007fff09980c10