INFO: task syz.0.737:8671 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.737 state:D stack:26824 pid:8671 tgid:8663 ppid:5866 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5360 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7046 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7061
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7118
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
bdev_open+0xe0/0xd30 block/bdev.c:945
bdev_file_open_by_dev+0x1be/0x240 block/bdev.c:1059
setup_bdev_super+0x5a/0x5b0 fs/super.c:1609
get_tree_bdev_flags+0x366/0x4d0 fs/super.c:1689
vfs_get_tree+0x92/0x2b0 fs/super.c:1751
fc_mount fs/namespace.c:1208 [inline]
do_new_mount_fc fs/namespace.c:3657 [inline]
do_new_mount+0x302/0xa10 fs/namespace.c:3733
do_mount fs/namespace.c:4056 [inline]
__do_sys_mount fs/namespace.c:4241 [inline]
__se_sys_mount+0x313/0x410 fs/namespace.c:4218
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9f34d8eba9
RSP: 002b:00007f9f35b3e038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f9f34fd6180 RCX: 00007f9f34d8eba9
RDX: 0000200000000080 RSI: 0000200000000000 RDI: 00002000000000c0
RBP: 00007f9f34e11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000008000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9f34fd6218 R14: 00007f9f34fd6180 R15: 00007fff07f02138
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e33d660 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e33d660 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e33d660 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:8/1344:
2 locks held by getty/5618:
#0: ffff888033e790a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/5848:
1 lock held by udevd/7016:
#0: ffff888025698358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
2 locks held by kworker/u8:12/7944:
#0: ffff88801df67948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
#0: ffff88801df67948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9001d31fba0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9001d31fba0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
2 locks held by kworker/u8:14/7946:
#0: ffff8880b863a018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:644
#1: ffff8880b8624048 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
2 locks held by syz.0.737/8671:
#0: ffff8880332ca0e0 (&type->s_umount_key#73/1){+.+.}-{4:4}, at: alloc_super+0x1bb/0x930 fs/super.c:344
#1: ffff888025698358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
2 locks held by syz.6.1214/10380:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7923 Comm: kworker/u8:11 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:rcu_lock_release include/linux/rcupdate.h:341 [inline]
RIP: 0010:rcu_read_unlock include/linux/rcupdate.h:871 [inline]
RIP: 0010:class_rcu_destructor include/linux/rcupdate.h:1169 [inline]
RIP: 0010:unwind_next_frame+0x199a/0x2390 arch/x86/kernel/unwind_orc.c:680
Code: 74 28 80 3d 90 2f 3a 0e 00 75 1f c6 05 87 2f 3a 0e 01 48 c7 c7 a0 60 a8 8b be 66 03 00 00 48 c7 c2 40 61 a8 8b e8 06 c4 29 00 <48> c7 c7 60 d6 33 8e 4c 89 fe e8 e7 a9 29 00 e8 62 4d 33 00 89 d8
RSP: 0018:ffffc9001d3af3f8 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff90db7f01 RCX: bbebed788e1abf00
RDX: ffffc9001d3af501 RSI: ffffffff8c0381e0 RDI: ffffffff8c0381a0
RBP: dffffc0000000000 R08: ffffc9001d3af918 R09: 0000000000000000
R10: ffffc9001d3af518 R11: fffff52003a75ea5 R12: ffffc9001d3af928
R13: ffffc9001d3a8000 R14: ffffc9001d3af4c8 R15: ffffffff8173bd25
FS: 0000000000000000(0000) GS:ffff888125ae0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000e7b030 CR3: 0000000078106000 CR4: 00000000003526f0
Call Trace:
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417
kasan_kmalloc include/linux/kasan.h:262 [inline]
__do_kmalloc_node mm/slub.c:5584 [inline]
__kmalloc_node_track_caller_noprof+0x568/0x800 mm/slub.c:5691
kmalloc_reserve+0x136/0x290 net/core/skbuff.c:600
__alloc_skb+0x142/0x2d0 net/core/skbuff.c:669
alloc_skb include/linux/skbuff.h:1377 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:763 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline]
nsim_dev_trap_report_work+0x29a/0xb80 drivers/net/netdevsim/dev.c:866
process_one_work kernel/workqueue.c:3263 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245