INFO: task syz.9.3169:19462 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.9.3169 state:D stack:28472 pid:19462 tgid:19453 ppid:15988 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1585/0x5340 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
blk_trace_startstop+0x8f/0x610 kernel/trace/blktrace.c:904
blk_trace_ioctl+0x314/0x920 kernel/trace/blktrace.c:950
blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724
blkdev_ioctl+0x528/0x740 block/ioctl.c:798
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
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: 0033:0x7f55ee59c629
RSP: 002b:00007f55ec3d3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f55ee816270 RCX: 00007f55ee59c629
RDX: 0000000000000000 RSI: 0000000000001274 RDI: 0000000000000009
RBP: 00007f55ee632b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f55ee816308 R14: 00007f55ee816270 R15: 00007f55ee93fa48
INFO: task syz.9.3169:19464 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.9.3169 state:D stack:28696 pid:19464 tgid:19453 ppid:15988 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1585/0x5340 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
blk_trace_remove kernel/trace/blktrace.c:562 [inline]
blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:953
blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724
blkdev_ioctl+0x528/0x740 block/ioctl.c:798
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
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: 0033:0x7f55ee59c629
RSP: 002b:00007f55ebfb0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f55ee816360 RCX: 00007f55ee59c629
RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000009
RBP: 00007f55ee632b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f55ee8163f8 R14: 00007f55ee816360 R15: 00007f55ee93fa48
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5587:
#0: ffff888031f860a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by dhcpcd/16071:
#0: ffff8880771afac8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff8880771afac8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: __sock_release net/socket.c:661 [inline]
#0: ffff8880771afac8 (&sb->s_type->i_mutex_key#14){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1455
#1: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
3 locks held by syz.9.3169/19455:
1 lock held by syz.9.3169/19462:
#0: ffff888025911bf0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff888025911bf0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_startstop+0x8f/0x610 kernel/trace/blktrace.c:904
1 lock held by syz.9.3169/19464:
#0: ffff888025911bf0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff888025911bf0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:562 [inline]
#0: ffff888025911bf0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:953
2 locks held by syz.0.3344/20129:
#0: ffff888025912578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff888025912578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline]
#0: ffff888025912578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:789
#1: ffffffff8e7bdf48 (relay_channels_mutex){+.+.}-{4:4}, at: relay_open+0x3b8/0x920 kernel/relay.c:516
1 lock held by syz.0.3344/20130:
#0: ffff888025912578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff888025912578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:562 [inline]
#0: ffff888025912578 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:953
2 locks held by syz.3.3417/20579:
#0: ffff888025911268 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline]
#0: ffff888025911268 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:752 [inline]
#0: ffff888025911268 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup2 kernel/trace/blktrace.c:824 [inline]
#0: ffff888025911268 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x6ec/0x920 kernel/trace/blktrace.c:934
#1: ffffffff8e7bdf48 (relay_channels_mutex){+.+.}-{4:4}, at: relay_open+0x3b8/0x920 kernel/relay.c:516
1 lock held by syz.7.3517/21368:
2 locks held by syz.8.3524/21418:
2 locks held by dhcpcd/21441:
#0: ffff888028674260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1709 [inline]
#0: ffff888028674260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x33/0xe10 net/packet/af_packet.c:3198
#1: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8e766578 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
1 lock held by sed/21447:
=============================================
NMI backtrace for cpu 1
CPU: 1 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 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: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 8e 6d 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 4d 1c 00 fb f4 7c ea 02 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8e407dc0 EFLAGS: 00000242
RAX: 00000000018747e9 RBX: ffffffff819a80dd RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8def18d2 RDI: ffffffff8c27a480
RBP: ffffffff8e407eb0 R08: ffff8880b863395b R09: 1ffff110170c672b
R10: dffffc0000000000 R11: ffffed10170c672c R12: ffffffff901172b0
R13: 1ffffffff1c929d8 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125466000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f143170ca90 CR3: 0000000079eb8000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1bd/0x500 kernel/sched/idle.c:332
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:430
rest_init+0x2de/0x300 init/main.c:760
start_kernel+0x385/0x3d0 init/main.c:1210
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147