INFO: task syz.0.3805:23120 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.3805 state:D stack:27800 pid:23120 tgid:23119 ppid:16538 task_flags:0x480140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820
blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
blk_debugfs_lock block/blk.h:770 [inline]
blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
blk_trace_ioctl+0x245/0x320 kernel/trace/blktrace.c:937
blkdev_ioctl+0x17c/0x6f0 block/ioctl.c:786
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x840 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7050d9ce59
RSP: 002b:00007f7051b8c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7051015fa0 RCX: 00007f7050d9ce59
RDX: 0000200000000340 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007f7050e32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7051016038 R14: 00007f7051015fa0 R15: 00007ffe1af5c318
INFO: task syz.0.3805:23121 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.3805 state:D stack:29032 pid:23121 tgid:23119 ppid:16538 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820
blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
blk_trace_remove kernel/trace/blktrace.c:561 [inline]
blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
blkdev_common_ioctl+0x170c/0x2b80 block/ioctl.c:717
blkdev_ioctl+0x43b/0x6f0 block/ioctl.c:791
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x840 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7050d9ce59
RSP: 002b:00007f704eff6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7051016090 RCX: 00007f7050d9ce59
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f7050e32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7051016128 R14: 00007f7051016090 R15: 00007ffe1af5c318
INFO: task syz.5.3791:23181 blocked for more than 145 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.3791 state:D stack:27304 pid:23181 tgid:23180 ppid:23047 task_flags:0x480140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820
blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
blk_debugfs_lock block/blk.h:770 [inline]
blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
blk_trace_ioctl+0x245/0x320 kernel/trace/blktrace.c:937
blkdev_ioctl+0x17c/0x6f0 block/ioctl.c:786
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x840 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f960a99ce59
RSP: 002b:00007f960b8d4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f960ac15fa0 RCX: 00007f960a99ce59
RDX: 0000200000000340 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007f960aa32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f960ac16038 R14: 00007f960ac15fa0 R15: 00007ffe5b378088
INFO: task syz.5.3791:23182 blocked for more than 146 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.3791 state:D stack:29032 pid:23182 tgid:23180 ppid:23047 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5388 [inline]
__schedule+0x1295/0x67a0 kernel/sched/core.c:7189
__schedule_loop kernel/sched/core.c:7268 [inline]
schedule+0xdd/0x390 kernel/sched/core.c:7283
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820
blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
blk_trace_remove kernel/trace/blktrace.c:561 [inline]
blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
blkdev_common_ioctl+0x170c/0x2b80 block/ioctl.c:717
blkdev_ioctl+0x43b/0x6f0 block/ioctl.c:791
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x840 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f960a99ce59
RSP: 002b:00007f960b8b3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f960ac16090 RCX: 00007f960a99ce59
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003
RBP: 00007f960aa32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f960ac16128 R14: 00007f960ac16090 R15: 00007ffe5b378088
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e7e53e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e7e53e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e7e53e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by getty/14427:
#0: ffff888037af70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000622b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211
3 locks held by kworker/u10:9/19337:
#0: ffff88813fe94140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289
#1: ffffc90004d0fd08 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290
#2: ffffffff906061e0 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:313
3 locks held by syz.4.3762/22905:
2 locks held by syz.3.3803/23111:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
#1: ffffffff8e8714e0 (relay_channels_mutex){+.+.}-{4:4}, at: relay_close kernel/relay.c:657 [inline]
#1: ffffffff8e8714e0 (relay_channels_mutex){+.+.}-{4:4}, at: relay_close+0x32/0x4b0 kernel/relay.c:649
1 lock held by syz.0.3805/23120:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:770 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.0.3805/23121:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.5.3791/23181:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:770 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.5.3791/23182:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.6.3815/23392:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:770 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.6.3815/23393:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.1.3834/23440:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:770 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.1.3834/23441:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.8.3851/23564:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:770 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.8.3851/23566:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.7.3865/23701:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:770 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.7.3865/23702:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
1 lock held by syz.2.3952/24207:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:770 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.2.3952/24208:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
2 locks held by syz.4.3963/24263:
#0: ffffffff905ed488 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575
#1: ffffffff906061e0 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x21e/0x780 net/ipv4/ip_tunnel.c:1146
1 lock held by syz.3.3968/24293:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:770 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x1f2/0x440 kernel/trace/blktrace.c:788
1 lock held by syz.3.3968/24294:
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline]
#0: ffff8880280f9b48 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x263/0x320 kernel/trace/blktrace.c:952
2 locks held by syz.9.3969/24305:
#0: ffffffff906061e0 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff906061e0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3441
#1: ffffffff8e7f0f28 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245