INFO: task syz.2.74:6196 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.74 state:D stack:29096 pid:6196 tgid:6190 ppid:5805 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5325 [inline]
__schedule+0x1190/0x5de0 kernel/sched/core.c:6929
__schedule_loop kernel/sched/core.c:7011 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:7026
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x818/0x1060 kernel/locking/mutex.c:760
blk_trace_startstop+0x7f/0x480 kernel/trace/blktrace.c:682
sg_ioctl_common drivers/scsi/sg.c:1118 [inline]
sg_ioctl+0xa3a/0x2880 drivers/scsi/sg.c:1156
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe7e9f8efc9
RSP: 002b:00007fe7ead55038 EFLAGS: 00000246
ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe7ea1e6090 RCX: 00007fe7e9f8efc9
RDX: 0000000000000000 RSI: 0000000000001274 RDI: 0000000000000003
RBP: 00007fe7ea011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe7ea1e6128 R14: 00007fe7ea1e6090 R15: 00007ffcdc863cd8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3c4460 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3c4460 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e3c4460 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6775
5 locks held by kworker/u8:5/177:
2 locks held by getty/5571:
#0: ffff8880357130a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1:
ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
6 locks held by kworker/1:3/5809:
#0:
ffff88802369f948 ((wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3238
#1:
ffffc900043afd00
(
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3239
#2:
ffff888144fb9198
(
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:914 [inline]
, at: hub_event+0x1c0/0x4fe0 drivers/usb/core/hub.c:5898
#3:
ffff88803090b198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
ffff88803090b198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#4: ffff88802e13e160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:914 [inline]
#4: ffff88802e13e160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1006
#5: ffff8881755600d0 (&d->usb_mutex){+.+.}-{4:4}, at: rtl28xxu_ctrl_msg+0x5d/0x780 drivers/media/usb/dvb-usb-v2/rtl28xxu.c:24
4 locks held by udevd/5965:
#0: ffff8881ac67a540 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12d0 fs/seq_file.c:182
#1: ffff888058cb5088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172
#2: ffff8881d207c5a8
(kn->active#24){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
(kn->active#24){++++}-{0:0}, at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173
#3: ffff88803090b198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:919 [inline]
#3: ffff88803090b198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
2 locks held by syz.2.74/6193:
1 lock held by syz.2.74/6196:
#0: ffff888142be6178 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_startstop+0x7f/0x480 kernel/trace/blktrace.c:682
=============================================
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 10/02/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/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+0xf3f/0x1170 kernel/hung_task.c:495
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x675/0x7d0 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: 6193 Comm: syz.2.74 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:lockdep_hardirqs_on+0x87/0x110 kernel/locking/lockdep.c:4474
Code: d2 75 10 48 8b 83 20 0b 00 00 48 39 83 08 0b 00 00 75 3a 48 c7 c7 87 a2 a2 8d e8 44 19 00 00 65 c7 05 75 5c 41 08 01 00 00 00 <8b> 83 c8 0a 00 00 48 89 ab d0 0a 00 00 83 c0 01 89 83 c8 0a 00 00
RSP: 0018:ffffc9000b7b7950 EFLAGS: 00000096
RAX: 0000000000000001 RBX: ffff8880342f0000 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffffffff8da2a287 RDI: ffffffff8bf06e40
RBP: ffffffff8b62fac2 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff9081f6d7 R11: 0000000000000001 R12: dffffc0000000000
R13: 000000000004a8f9 R14: 0000000000000000 R15: ffffc9001ee89000
FS: 00007fe7ead766c0(0000) GS:ffff888124b0a000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcda89b3ad8 CR3: 0000000074ae1000 CR4: 00000000003526f0
Call Trace:
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
_raw_spin_unlock_irqrestore+0x52/0x80 kernel/locking/spinlock.c:194
__debug_check_no_obj_freed lib/debugobjects.c:1108 [inline]
debug_check_no_obj_freed+0x31f/0x600 lib/debugobjects.c:1129
remove_vm_area+0x1ae/0x3f0 mm/vmalloc.c:3297
vunmap mm/vmalloc.c:3468 [inline]
vunmap+0x55/0xa0 mm/vmalloc.c:3459
relay_destroy_buf+0x72/0x3e0 kernel/relay.c:198
relay_remove_buf kernel/relay.c:220 [inline]
kref_put include/linux/kref.h:65 [inline]
relay_close_buf+0x144/0x1a0 kernel/relay.c:435
relay_open+0x765/0xad0 kernel/relay.c:531
do_blk_trace_setup+0x4c5/0xb00 kernel/trace/blktrace.c:572
blk_trace_setup+0xed/0x1b0 kernel/trace/blktrace.c:614
sg_ioctl_common drivers/scsi/sg.c:1114 [inline]
sg_ioctl+0x7d7/0x2880 drivers/scsi/sg.c:1156
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl fs/ioctl.c:583 [inline]
__x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe7e9f8efc9
Code: Unable to access opcode bytes at 0x7fe7e9f8ef9f.
RSP: 002b:00007fe7ead76038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe7ea1e5fa0 RCX: 00007fe7e9f8efc9
RDX: 0000200000000b40 RSI: 00000000c0481273 RDI: 0000000000000003
RBP: 00007fe7ea011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fe7ea1e6038 R14: 00007fe7ea1e5fa0 R15: 00007ffcdc863cd8