INFO: task syz.1.604:7910 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.1.604 state:D stack:26832 pid:7910 tgid:7906 ppid:5843 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5352 [inline]
__schedule+0x1665/0x5590 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7047 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7062
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7119
rwsem_down_write_slowpath+0x883/0x1080 kernel/locking/rwsem.c:1215
__down_write_common kernel/locking/rwsem.c:1347 [inline]
__down_write kernel/locking/rwsem.c:1356 [inline]
down_write+0x1bc/0x200 kernel/locking/rwsem.c:1626
inode_lock include/linux/fs.h:1028 [inline]
vfs_unlink+0xed/0x6c0 fs/namei.c:5478
filename_unlinkat+0x3cd/0x610 fs/namei.c:5562
__do_sys_unlinkat fs/namei.c:5591 [inline]
__se_sys_unlinkat+0x83/0x1a0 fs/namei.c:5583
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: 0033:0x7fdab499c799
RSP: 002b:00007fdab58a2028 EFLAGS: 00000246 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 00007fdab4c16090 RCX: 00007fdab499c799
RDX: 0000000000000000 RSI: 00002000000011c0 RDI: 0000000000000003
RBP: 00007fdab4a32c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdab4c16128 R14: 00007fdab4c16090 R15: 00007ffdf8a57a08
INFO: task syz.1.604:7912 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.1.604 state:D stack:27472 pid:7912 tgid:7906 ppid:5843 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5352 [inline]
__schedule+0x1665/0x5590 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7047 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7062
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7119
rwsem_down_write_slowpath+0x883/0x1080 kernel/locking/rwsem.c:1215
__down_write_common kernel/locking/rwsem.c:1347 [inline]
__down_write kernel/locking/rwsem.c:1356 [inline]
down_write+0x1bc/0x200 kernel/locking/rwsem.c:1626
inode_lock include/linux/fs.h:1028 [inline]
do_lock_mount+0x2b3/0x960 fs/namespace.c:2763
do_new_mount_fc fs/namespace.c:3782 [inline]
do_new_mount+0x483/0xd30 fs/namespace.c:3840
do_mount fs/namespace.c:4173 [inline]
__do_sys_mount fs/namespace.c:4372 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4349
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: 0033:0x7fdab499c799
RSP: 002b:00007fdab5881028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fdab4c16180 RCX: 00007fdab499c799
RDX: 0000200000000300 RSI: 00002000000001c0 RDI: 0000000000000000
RBP: 00007fdab4a32c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdab4c16218 R14: 00007fdab4c16180 R15: 00007ffdf8a57a08
Showing all locks held in the system:
5 locks held by kworker/0:0/9:
3 locks held by kworker/u8:0/12:
#0: ffff88813fe44140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc90000117c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffffffff8fff66c0 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
1 lock held by khungtaskd/30:
#0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
3 locks held by kworker/1:2/1223:
#0: ffff88801ee99940 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc9000598fc40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffff88802a58d190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#2: ffff88802a58d190 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899
2 locks held by getty/5606:
#0: ffff888036df60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
3 locks held by syz.1.604/7910:
#0: ffff88802b830410 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff88805980b9a0 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff88805980b9a0 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2908 [inline]
#1: ffff88805980b9a0 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2932 [inline]
#1: ffff88805980b9a0 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: filename_unlinkat+0x2a7/0x610 fs/namei.c:5543
#2: ffff8880333b4c00 (&sb->s_type->i_mutex_key#15){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#2: ffff8880333b4c00 (&sb->s_type->i_mutex_key#15){+.+.}-{4:4}, at: vfs_unlink+0xed/0x6c0 fs/namei.c:5478
1 lock held by syz.1.604/7912:
#0: ffff8880333b4c00 (&sb->s_type->i_mutex_key#15){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#0: ffff8880333b4c00 (&sb->s_type->i_mutex_key#15){+.+.}-{4:4}, at: do_lock_mount+0x2b3/0x960 fs/namespace.c:2763
2 locks held by syz.4.1771/12400:
#0: ffffffff8fff66c0 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fff66c0 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
#1: ffffffff8eb638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8eb638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961
1 lock held by sed/12417:
=============================================
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_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: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+0x1002/0x1060 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
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: 138 Comm: kworker/u8:5 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4854 [inline]
RIP: 0010:__lock_acquire+0x3ac/0x2cf0 kernel/locking/lockdep.c:5187
Code: 27 90 e8 67 1d 15 03 85 c0 74 1c 83 3d a0 8e b1 0e 00 75 13 48 8d 3d c3 b1 b4 0e 48 c7 c6 23 8a 37 8e 67 48 0f b9 3a 90 31 c0 <0f> b6 98 c4 00 00 00 41 8b 45 20 25 ff 1f 00 00 48 0f a3 05 4c da
RSP: 0018:ffffc90002ed72f8 EFLAGS: 00000006
RAX: ffffffff940cc8a8 RBX: 0000000000020000 RCX: 0000000000000007
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000004 R08: ffffffff81778bb5 R09: ffffffff8eb5d6a0
R10: ffffc90002ed7638 R11: fffff520005daec9 R12: 0000000000000007
R13: ffff88801fbec8f0 R14: ffff88801fbebd00 R15: ffff88801fbec850
FS: 0000000000000000(0000) GS:ffff888124de1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffca40f4358 CR3: 000000004b774000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0xf0/0x2e0 kernel/locking/lockdep.c:5868
rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
rcu_read_lock include/linux/rcupdate.h:850 [inline]
class_rcu_constructor include/linux/rcupdate.h:1193 [inline]
unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495
__unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:773
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5292 [inline]
__kmalloc_node_track_caller_noprof+0x4db/0x7b0 mm/slub.c:5400
kmalloc_reserve net/core/skbuff.c:635 [inline]
__alloc_skb+0x2c1/0x7d0 net/core/skbuff.c:713
alloc_skb include/linux/skbuff.h:1383 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline]
nsim_dev_trap_report_work+0x29a/0xb80 drivers/net/netdevsim/dev.c:922
process_one_work+0x9ab/0x1780 kernel/workqueue.c:3289
process_scheduled_works kernel/workqueue.c:3380 [inline]
worker_thread+0xba8/0x11e0 kernel/workqueue.c:3466
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245