INFO: task syz.8.6304:30480 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.8.6304 state:D stack:25696 pid:30480 tgid:30480 ppid:29158 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 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+0xc9a/0x1b90 kernel/locking/mutex.c:776
bdev_release+0x15a/0x6d0 block/bdev.c:1144
blkdev_release+0x15/0x20 block/fops.c:705
__fput+0x3ff/0xb40 fs/file_table.c:469
task_work_run+0x150/0x240 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faa0d19c629
RSP: 002b:00007fff3fa7d7c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007faa0d417da0 RCX: 00007faa0d19c629
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007faa0d417da0 R08: 0000000000000006 R09: 0000000000000000
R10: 00007faa0d417cb0 R11: 0000000000000246 R12: 00000000001b8f7b
R13: 00007faa0d41636c R14: 00000000001b8e68 R15: 00007faa0d416360
INFO: task syz.8.6304:30485 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.8.6304 state:D
stack:28304 pid:30485 tgid:30480 ppid:29158 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0xfee/0x60e0 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0xdd/0x390 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+0xc9a/0x1b90 kernel/locking/mutex.c:776
bdev_release+0x15a/0x6d0 block/bdev.c:1144
blkdev_release+0x15/0x20 block/fops.c:705
__fput+0x3ff/0xb40 fs/file_table.c:469
task_work_run+0x150/0x240 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0x100/0x4a0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faa0d19c629
RSP: 002b:00007faa0e0f3028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007faa0d416090 RCX: 00007faa0d19c629
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000004
RBP: 00007faa0d232b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007faa0d416128 R14: 00007faa0d416090 R15: 00007fff3fa7d668
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e7e93e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e7e93e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e7e93e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by getty/5566:
#0: ffff8880391f90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
1 lock held by udevd/27248:
#0: ffff88802848f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:961
1 lock held by syz-executor/29517:
#0: ffffffff8e7f4ff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by syz.8.6304/30480:
#0: ffff88802848f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x15a/0x6d0 block/bdev.c:1144
1 lock held by syz.8.6304/30485:
#0: ffff88802848f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x15a/0x6d0 block/bdev.c:1144
2 locks held by syz.9.6937/525:
#0: ffffffff9060f5e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff9060f5e8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x220 drivers/net/tun.c:3436
#1: ffffffff8e7f4ff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311
2 locks held by syz.0.6933/546:
#0: ffffffff9b653f78 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnl_lock net/netfilter/nfnetlink.c:98 [inline]
#0: ffffffff9b653f78 (nfnl_subsys_nftables){+.+.}-{4:4}, at: nfnetlink_rcv_batch+0x285/0x2880 net/netfilter/nfnetlink.c:394
#1: ffff8880349ce8d8 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x35/0x140 net/netfilter/nf_tables_api.c:11422
1 lock held by syz.0.6933/547:
#0: ffff8880349ce8d8 (&nft_net->commit_mutex){+.+.}-{4:4}, at: nf_tables_valid_genid+0x35/0x140 net/netfilter/nf_tables_api.c:11422
1 lock held by dhcpcd/542:
#0: ffff888074720208 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff888074720208 (&sb->s_type->i_mutex_key#13){+.+.}-{4:4}, at: __sock_release+0x86/0x260 net/socket.c:661
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 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 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:161 [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:346 [inline]
watchdog+0xd25/0x1050 kernel/hung_task.c:515
kthread+0x370/0x450 kernel/kthread.c:467
ret_from_fork+0x754/0xd80 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: 511 Comm: syz.6.6932 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:__sanitizer_cov_trace_const_cmp8+0x0/0x20 kernel/kcov.c:320
Code: 0c 24 89 f2 89 fe bf 05 00 00 00 e9 2a fe ff ff 66 2e 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 0c 24 48 89 f2 48 89 fe bf 07 00 00 00 e9 f8 fd
RSP: 0000:ffffc900026c7b08 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff888031982480 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888031982480 R08: 0000000000000001 R09: 00000000000001c8
R10: 0000000000000200 R11: 0000000000000000 R12: 00007ffffffff000
R13: 00007ffeb233e980 R14: 00007ffeb233e980 R15: ffff888031983e40
FS: 000055556f0a6500(0000) GS:ffff888124348000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0a8a3e89b8 CR3: 000000003024f000 CR4: 00000000003526f0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
copy_fpstate_to_sigframe+0x188/0xb20 arch/x86/kernel/fpu/signal.c:203
get_sigframe+0x3fb/0x940 arch/x86/kernel/signal.c:163
x64_setup_rt_frame+0x12f/0xce0 arch/x86/kernel/signal_64.c:175
setup_rt_frame arch/x86/kernel/signal.c:250 [inline]
handle_signal arch/x86/kernel/signal.c:294 [inline]
arch_do_signal_or_restart+0x59e/0x7a0 arch/x86/kernel/signal.c:339
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop kernel/entry/common.c:98 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x1f8/0x670 kernel/entry/common.c:219
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0033:0x7f2cf666cb6d
Code: 08 48 83 c3 08 48 39 d1 72 f3 48 8d 46 f8 48 8b 76 f8 48 39 f2 73 13 66 0f 1f 44 00 00 48 8b 70 f8 48 83 e8 08 48 39 f2 72 f3 <48> 39 c3 73 3e 48 89 33 48 89 c6 48 83 c3 08 48 89 08 48 8b 0b 48
RSP: 002b:00007ffeb233f4b0 EFLAGS: 00000246
RAX: 00007f2cf6203cc0 RBX: 00007f2cf6203c50 RCX: ffffffff81aa4db5
RDX: ffffffff81aa4da7 RSI: ffffffff81aa4da7 RDI: 00007f2cf6203c98
RBP: 00007f2cf6203be8 R08: 00007f2cf6a00000 R09: 00007f2cf6a16038
R10: 0000000000000007 R11: 0000000000000003 R12: 00007f2cf6203d50
R13: 0000000000000011 R14: 000000000000002d R15: 0000000000000007