INFO: task syz.2.200:7403 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kerne[ 365.236025][ T38] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.200 state:D stack:28392 pid:7403 tgid:7357 ppid:5801 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x145f/0x5070 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760
__rwbase_read_lock+0xbc/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1466 [inline]
down_read+0x127/0x1f0 kernel/locking/rwsem.c:1539
inode_lock_shared include/linux/fs.h:1042 [inline]
lookup_slow+0x46/0x70 fs/namei.c:1874
walk_component fs/namei.c:2221 [inline]
link_path_walk+0xd1e/0x18d0 fs/namei.c:2589
path_lookupat+0xe4/0x8c0 fs/namei.c:2745
filename_lookup+0x212/0x570 fs/namei.c:2775
vfs_statx+0xf8/0x550 fs/stat.c:353
vfs_fstatat fs/stat.c:375 [inline]
vfs_lstat include/linux/fs.h:3161 [inline]
__do_sys_newlstat fs/stat.c:528 [inline]
__se_sys_newlstat fs/stat.c:522 [inline]
__x64_sys_newlstat+0xea/0x170 fs/stat.c:522
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc6562cf749
RSP: 002b:00007fc6544ec038 EFLAGS: 00000246 ORIG_RAX: 0000000000000006
RAX: ffffffffffffffda RBX: 00007fc656526180 RCX: 00007fc6562cf749
RDX: 0000000000000000 RSI: 0000200000000740 RDI: 0000200000000680
RBP: 00007fc656353f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc656526218 R14: 00007fc656526180 R15: 00007ffe10e3a198
INFO: task syz.2.200:7407 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.200 state:D stack:28912 pid:7407 tgid:7357 ppid:5801 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x145f/0x5070 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760
__rwbase_read_lock+0xbc/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1466 [inline]
down_read+0x127/0x1f0 kernel/locking/rwsem.c:1539
inode_lock_shared include/linux/fs.h:1042 [inline]
lookup_slow+0x46/0x70 fs/namei.c:1874
walk_component fs/namei.c:2221 [inline]
link_path_walk+0xd1e/0x18d0 fs/namei.c:2589
path_lookupat+0xe4/0x8c0 fs/namei.c:2745
filename_lookup+0x212/0x570 fs/namei.c:2775
user_path_at+0x3a/0x60 fs/namei.c:3567
do_fchownat+0x105/0x270 fs/open.c:813
__do_sys_chown fs/open.c:839 [inline]
__se_sys_chown fs/open.c:837 [inline]
__x64_sys_chown+0x82/0xa0 fs/open.c:837
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc6562cf749
RSP: 002b:00007fc6540c9038 EFLAGS: 00000246 ORIG_RAX: 000000000000005c
RAX: ffffffffffffffda RBX: 00007fc656526270 RCX: 00007fc6562cf749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00002000000006c0
RBP: 00007fc656353f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc656526308 R14: 00007fc656526270 R15: 00007ffe10e3a198
INFO: task syz.2.200:7408 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.200 state:D stack:28088 pid:7408 tgid:7357 ppid:5801 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x145f/0x5070 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7241
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1dfe/0x25e0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
inode_lock_nested include/linux/fs.h:1072 [inline]
__start_dirop fs/namei.c:2864 [inline]
start_dirop fs/namei.c:2875 [inline]
filename_create+0x1fb/0x360 fs/namei.c:4879
do_mkdirat+0xca/0x4b0 fs/namei.c:5156
__do_sys_mkdirat fs/namei.c:5186 [inline]
__se_sys_mkdirat fs/namei.c:5184 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:5184
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc6562cde97
RSP: 002b:00007fc653ca5e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fc653ca5ef0 RCX: 00007fc6562cde97
RDX: 00000000000001ff RSI: 00002000000000c0 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000000c0
R13: 00007fc653ca5eb0 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813ff69938 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc90000127bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc90000127bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8e8a5af8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
4 locks held by pr/legacy/17:
1 lock held by khungtaskd/38:
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8d5ae940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by dhcpcd/5464:
#0: ffff88803974a928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xbd/0xe90 net/netlink/af_netlink.c:2267
#1: ffffffff8e8a5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8e8a5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6826
2 locks held by getty/5555:
#0: ffff88814e4150a0 (&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+0x44f/0x1460 drivers/tty/n_tty.c:2211
3 locks held by kworker/0:3/5757:
#0: ffff88813ff55138 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff88813ff55138 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc9000486fbc0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000486fbc0 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffffffff8e8a5af8 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
1 lock held by syz-executor/5807:
#0: ffff888062dde0d0 (&type->s_umount_key#61){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff888062dde0d0 (&type->s_umount_key#61){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff888062dde0d0 (&type->s_umount_key#61){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
3 locks held by kworker/1:6/5889:
4 locks held by kworker/u8:21/7324:
#0: ffff888140473938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3232 [inline]
#0: ffff888140473938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x1770 kernel/workqueue.c:3340
#1: ffffc9000521fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3233 [inline]
#1: ffffc9000521fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x1770 kernel/workqueue.c:3340
#2: ffff888057e880d0 (&type->s_umount_key#78){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff888059eb59a8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
4 locks held by syz.2.200/7359:
1 lock held by syz.2.200/7403:
#0: ffff888059eb5d78 (&type->i_mutex_dir_key#19){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline]
#0: ffff888059eb5d78 (&type->i_mutex_dir_key#19){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1874
1 lock held by syz.2.200/7407:
#0: ffff888059eb5d78 (&type->i_mutex_dir_key#19){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1042 [inline]
#0: ffff888059eb5d78 (&type->i_mutex_dir_key#19){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1874
2 locks held by syz.2.200/7408:
#0: ffff888057e88480 (sb_writers#24){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
#1: ffff888059eb5d78 (&type->i_mutex_dir_key#19/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1072 [inline]
#1: ffff888059eb5d78 (&type->i_mutex_dir_key#19/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2864 [inline]
#1: ffff888059eb5d78 (&type->i_mutex_dir_key#19/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2875 [inline]
#1: ffff888059eb5d78 (&type->i_mutex_dir_key#19/1){+.+.}-{4:4}, at: filename_create+0x1fb/0x360 fs/namei.c:4879
6 locks held by kworker/u8:23/8216:
2 locks held by syz-executor/8955:
#0: ffffffff8edb5040 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8edb5040 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8edb5040 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8e8a5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8e8a5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8e8a5af8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8ec/0x1c90 net/core/rtnetlink.c:4071
2 locks held by syz.5.425/9029:
2 locks held by syz.7.424/9036:
=============================================
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 10/25/2025
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:160 [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+0xf95/0xfe0 kernel/hung_task.c:515
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:rdtsc_ordered arch/x86/include/asm/tsc.h:57 [inline]
RIP: 0010:delay_tsc+0x71/0xc0 arch/x86/lib/delay.c:72
Code: 00 00 e8 72 20 c0 f6 65 8b 05 bb cc e2 06 85 c0 74 1c f3 90 bf 01 00 00 00 e8 bb 1e c0 f6 e8 26 78 01 00 39 c5 75 0e 0f 01 f9 <66> 90 eb bd e8 d6 d3 62 f6 eb dd 4c 29 fb e8 0c 78 01 00 89 c5 0f
RSP: 0018:ffffc90000167950 EFLAGS: 00000246
RAX: 000000008e7a112c RBX: 0000000000000899 RCX: 0000000000000000
RDX: 00000000000000bd RSI: ffffffff8b3f57c0 RDI: ffffffff8b3f5780
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff8ad04320 R12: 1ffffffff31f3602
R13: 00000000ffffffff R14: 000000bd8e7a085a R15: 000000000000084a
FS: 0000000000000000(0000) GS:ffff888126cef000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fed1dea1000 CR3: 000000000d3a8000 CR4: 00000000003526f0
Call Trace:
udelay include/asm-generic/delay.h:62 [inline]
wait_for_lsr+0x166/0x2f0 drivers/tty/serial/8250/8250_port.c:1967
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline]
serial8250_console_write+0x11bd/0x1b40 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3109 [inline]
console_flush_one_record+0x685/0xb80 kernel/printk/printk.c:3215
legacy_kthread_func+0x16f/0x210 kernel/printk/printk.c:3674
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246