INFO: task syz.0.1770:11808 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1770 state:D stack:25696 pid:11808 tgid:11808 ppid:5845 task_flags:0x40004c flags:0x00080000
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_read_slowpath+0x6d9/0x940 kernel/locking/rwsem.c:1114
__down_read_common kernel/locking/rwsem.c:1291 [inline]
__down_read kernel/locking/rwsem.c:1304 [inline]
down_read+0x99/0x2e0 kernel/locking/rwsem.c:1570
mmap_read_lock include/linux/mmap_lock.h:592 [inline]
exit_mm+0x73/0x250 kernel/exit.c:557
do_exit+0x8b9/0x2490 kernel/exit.c:962
do_group_exit+0x21b/0x2d0 kernel/exit.c:1116
__do_sys_exit_group kernel/exit.c:1127 [inline]
__se_sys_exit_group kernel/exit.c:1125 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1125
x64_sys_call+0x221a/0x2240 arch/x86/include/generated/asm/syscalls_64.h:232
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: 0033:0x7fd33fb9c799
RSP: 002b:00007ffe73a3ef78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 000000000000000b RCX: 00007fd33fb9c799
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 0000000000001793 R08: 00007ffe73a3f417 R09: 000000000000000b
R10: 00007fd33fe15fa0 R11: 0000000000000246 R12: 0000000000000003
R13: 00007fd33fe1627c R14: 00007fd33fe16278 R15: 00007fd33fe16270
INFO: task syz.0.1770:11812 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1770 state:D stack:28800 pid:11812 tgid:11808 ppid:5845 task_flags:0x40044c flags:0x00080000
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_read_slowpath+0x6d9/0x940 kernel/locking/rwsem.c:1114
__down_read_common kernel/locking/rwsem.c:1291 [inline]
__down_read kernel/locking/rwsem.c:1304 [inline]
down_read+0x99/0x2e0 kernel/locking/rwsem.c:1570
mmap_read_lock include/linux/mmap_lock.h:592 [inline]
exit_mm+0x73/0x250 kernel/exit.c:557
do_exit+0x8b9/0x2490 kernel/exit.c:962
do_group_exit+0x21b/0x2d0 kernel/exit.c:1116
get_signal+0x1284/0x1330 kernel/signal.c:3035
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__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:238 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:283 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:352 [inline]
irqentry_exit+0x188/0x700 kernel/entry/common.c:219
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fd33fb4acdf
RSP: 002b:00007fd340adaff0 EFLAGS: 00010246
RAX: 00007fd340adb0d0 RBX: 0000000000020000 RCX: 00007fd340adaff0
RDX: 00007fd33fc4eddd RSI: 0000000000000023 RDI: 00007fd340adb0d0
RBP: 00007fd340abc000 R08: 0000000000000000 R09: 00007ffe73a3f417
R10: 0000000000000008 R11: 0000000000000202 R12: 00007fd340adb0d0
R13: 000000000000000b R14: 00007ffe73a3f330 R15: 00007ffe73a3f418
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#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
2 locks held by getty/5605:
#0: ffff88803794a0a0 (&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
5 locks held by kworker/0:7/5912:
#0: ffff8880222ab540 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc90004c97c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffff88802b149190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#2: ffff88802b149190 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899
#3: ffff88807e4b3190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#3: ffff88807e4b3190 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1008
#4: ffff888057fb7158 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#4: ffff888057fb7158 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1008
4 locks held by udevd/6479:
#0: ffff888036d842d8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:183
#1: ffff888068637c80 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172
#2: ffff888065ea1008 (kn->active#29){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888065ea1008 (kn->active#29){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173
#3: ffff88807e4b3190 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:946 [inline]
#3: ffff88807e4b3190 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
1 lock held by syz.0.1770/11808:
#0: ffff88802a9173b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline]
#0: ffff88802a9173b8 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0x73/0x250 kernel/exit.c:557
1 lock held by syz.0.1770/11812:
#0: ffff88802a9173b8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline]
#0: ffff88802a9173b8 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0x73/0x250 kernel/exit.c:557
4 locks held by syz.3.2671/15003:
#0: ffffffff90064bc8 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff90064a00 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline]
#1: ffffffff90064a00 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline]
#1: ffffffff90064a00 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10b/0x7a0 net/netlink/genetlink.c:1208
#2: ffff88807e4b60f8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#2: ffff88807e4b60f8 (&dev->mutex){....}-{4:4}, at: nfc_dev_up+0x3f/0x350 net/nfc/core.c:95
#3: ffff88801fb4e348 (&ndev->req_lock){+.+.}-{4:4}, at: nci_open_device net/nfc/nci/core.c:478 [inline]
#3: ffff88801fb4e348 (&ndev->req_lock){+.+.}-{4:4}, at: nci_dev_up+0xa3/0xdd0 net/nfc/nci/core.c:641
=============================================
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: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: 1097 Comm: kworker/u8:7 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:on_stack arch/x86/include/asm/stacktrace.h:60 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:409 [inline]
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:419 [inline]
RIP: 0010:unwind_next_frame+0xd77/0x23c0 arch/x86/kernel/unwind_orc.c:600
Code: b6 04 01 84 c0 0f 85 51 11 00 00 41 83 3e 00 0f 95 c0 49 39 df 0f 96 c1 20 c1 49 39 dc 0f 97 c0 20 c8 3c 01 75 18 48 8d 43 08 <4c> 39 f8 0f 97 c1 4c 39 e0 0f 96 c0 84 c1 0f 85 bf 00 00 00 49 8d
RSP: 0018:ffffc9000582f4b8 EFLAGS: 00000246
RAX: ffffc9000582fb40 RBX: ffffc9000582fb38 RCX: 1ffff92000b05e01
RDX: ffffffff9149571c RSI: 0000000000000002 RDI: ffffffff8c4a6220
RBP: 1ffff92000b05eb2 R08: 0000000000000001 R09: ffffffff8eb5d6a0
R10: ffffc9000582f5d8 R11: ffffffff81b21b20 R12: ffffc90005830000
R13: 1ffff92000b05eb3 R14: ffffc9000582f588 R15: ffffc90005828000
FS: 0000000000000000(0000) GS:ffff888124de1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa5c95e92f8 CR3: 0000000075410000 CR4: 00000000003526f0
Call Trace:
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
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
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2689 [inline]
slab_free mm/slub.c:6242 [inline]
kfree+0x1c5/0x650 mm/slub.c:6557
skb_kfree_head net/core/skbuff.c:1078 [inline]
skb_free_head net/core/skbuff.c:1090 [inline]
skb_release_data+0x848/0xa80 net/core/skbuff.c:1117
skb_release_all net/core/skbuff.c:1192 [inline]
__kfree_skb+0x5d/0x210 net/core/skbuff.c:1206
nsim_dev_trap_report drivers/net/netdevsim/dev.c:892 [inline]
nsim_dev_trap_report_work+0x7cf/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