INFO: task syz.5.1349:10995 blocked for more than 143 seconds.
Not tainted 6.14.0-syzkaller-03576-g1e1ba8d23dae #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.1349 state:D stack:26984 pid:10995 tgid:10990 ppid:6704 task_flags:0x400140 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5366 [inline]
__schedule+0x1b18/0x50e0 kernel/sched/core.c:6747
__schedule_loop kernel/sched/core.c:6824 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6839
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6896
__mutex_lock_common kernel/locking/mutex.c:664 [inline]
__mutex_lock+0x7fa/0x1000 kernel/locking/mutex.c:732
device_lock include/linux/device.h:922 [inline]
usbdev_open+0x155/0x790 drivers/usb/core/devio.c:1054
chrdev_open+0x514/0x600 fs/char_dev.c:414
do_dentry_open+0xdec/0x1960 fs/open.c:956
vfs_open+0x3b/0x370 fs/open.c:1086
do_open fs/namei.c:3845 [inline]
path_openat+0x2caf/0x35d0 fs/namei.c:4004
do_filp_open+0x284/0x4e0 fs/namei.c:4031
do_sys_openat2+0x12b/0x1d0 fs/open.c:1429
do_sys_open fs/open.c:1444 [inline]
__do_sys_openat fs/open.c:1460 [inline]
__se_sys_openat fs/open.c:1455 [inline]
__x64_sys_openat+0x249/0x2a0 fs/open.c:1455
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd61b58bad0
RSP: 002b:00007fd61c40bb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fd61b58bad0
RDX: 0000000000000002 RSI: 00007fd61c40bc10 RDI: 00000000ffffff9c
RBP: 00007fd61c40bc10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fd61b7a6080 R15: 00007fd61b8cfa28
INFO: task syz.2.1358:11025 blocked for more than 144 seconds.
Not tainted 6.14.0-syzkaller-03576-g1e1ba8d23dae #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1358 state:D stack:26800 pid:11025 tgid:11024 ppid:5851 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5366 [inline]
__schedule+0x1b18/0x50e0 kernel/sched/core.c:6747
__schedule_loop kernel/sched/core.c:6824 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6839
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6896
__mutex_lock_common kernel/locking/mutex.c:664 [inline]
__mutex_lock+0x7fa/0x1000 kernel/locking/mutex.c:732
device_lock include/linux/device.h:922 [inline]
usbdev_open+0x155/0x790 drivers/usb/core/devio.c:1054
chrdev_open+0x514/0x600 fs/char_dev.c:414
do_dentry_open+0xdec/0x1960 fs/open.c:956
vfs_open+0x3b/0x370 fs/open.c:1086
do_open fs/namei.c:3845 [inline]
path_openat+0x2caf/0x35d0 fs/namei.c:4004
do_filp_open+0x284/0x4e0 fs/namei.c:4031
do_sys_openat2+0x12b/0x1d0 fs/open.c:1429
do_sys_open fs/open.c:1444 [inline]
__do_sys_openat fs/open.c:1460 [inline]
__se_sys_openat fs/open.c:1455 [inline]
__x64_sys_openat+0x249/0x2a0 fs/open.c:1455
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f799738bad0
RSP: 002b:00007f7998274b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000000000000a401 RCX: 00007f799738bad0
RDX: 000000000000a401 RSI: 00007f7998274c10 RDI: 00000000ffffff9c
RBP: 00007f7998274c10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f79975a5fa0 R15: 00007f79976cfa28
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8eb3a860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8eb3a860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8eb3a860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6761
2 locks held by getty/5594:
#0: ffff88803579a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000330b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x53d/0x16b0 drivers/tty/n_tty.c:2211
4 locks held by udevd/5848:
#0: ffff88804fff38b8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb4/0xda0 fs/seq_file.c:182
#1: ffff888031277c88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154
#2: ffff888030f04a58 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155
#3: ffff888033740190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#3: ffff888033740190 (&dev->mutex){....}-{4:4}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2730
4 locks held by udevd/5849:
#0: ffff88802714f418 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb4/0xda0 fs/seq_file.c:182
#1: ffff88804e042888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154
#2: ffff888030f04a58 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155
#3: ffff888033740190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#3: ffff888033740190 (&dev->mutex){....}-{4:4}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2730
6 locks held by kworker/1:5/5889:
#0: ffff888140e8f548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888140e8f548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc9000447fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000447fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffff888145b7e190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#2: ffff888145b7e190 (&dev->mutex){....}-{4:4}, at: hub_event+0x200/0x50f0 drivers/usb/core/hub.c:5861
#3: ffff888033740190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#3: ffff888033740190 (&dev->mutex){....}-{4:4}, at: __device_attach+0x90/0x530 drivers/base/dd.c:1005
#4: ffff88807cd3d160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#4: ffff88807cd3d160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x90/0x530 drivers/base/dd.c:1005
#5: ffffffff8e9e3570 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0x142/0x300 kernel/umh.c:214
4 locks held by udevd/5943:
#0: ffff888039577790 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb4/0xda0 fs/seq_file.c:182
#1: ffff88807d5cc888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154
#2: ffff888039c1f878 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155
#3: ffff88807cd3d160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#3: ffff88807cd3d160 (&dev->mutex){....}-{4:4}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2730
4 locks held by udevd/6436:
#0: ffff8880562239e0 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb4/0xda0 fs/seq_file.c:182
#1: ffff888011d62488 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154
#2: ffff888030f04a58 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155
#3: ffff888033740190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#3: ffff888033740190 (&dev->mutex){....}-{4:4}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2730
1 lock held by syz.5.1349/10995:
#0: ffff888145b7e190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#0: ffff888145b7e190 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x155/0x790 drivers/usb/core/devio.c:1054
1 lock held by syz.2.1358/11025:
#0: ffff888145b7e190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#0: ffff888145b7e190 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x155/0x790 drivers/usb/core/devio.c:1054
1 lock held by syz.0.1532/11627:
#0: ffff888145b7e190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#0: ffff888145b7e190 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x155/0x790 drivers/usb/core/devio.c:1054
1 lock held by syz.6.1753/12504:
#0: ffff888145b7e190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#0: ffff888145b7e190 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x155/0x790 drivers/usb/core/devio.c:1054
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-syzkaller-03576-g1e1ba8d23dae #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:399
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
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: 5884 Comm: kworker/0:5 Not tainted 6.14.0-syzkaller-03576-g1e1ba8d23dae #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events_power_efficient neigh_periodic_work
RIP: 0010:__alloc_skb+0x25d/0x480 net/core/skbuff.c:622
Code: f7 31 f6 e8 85 1f 5a f8 4c 89 f7 4c 89 fe 89 da e8 d8 f0 ff ff 48 8b 44 24 30 42 0f b6 04 28 84 c0 4c 89 eb 0f 85 90 01 00 00 <44> 0f b6 6c 24 70 4d 8d 7e 7e 4d 89 fc 49 c1 ec 03 41 0f b6 04 1c
RSP: 0018:ffffc9000442f960 EFLAGS: 00000297
RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffffc9000442f900
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff88803904dee0
RBP: ffffc9000442fa28 R08: ffff88803904dee3 R09: 1ffff11007209bdc
R10: dffffc0000000000 R11: ffffed1007209bdd R12: 0000000000000000
R13: dffffc0000000000 R14: ffff8880384c3780 R15: ffff88803904dd40
FS: 0000000000000000(0000) GS:ffff888125224000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdd4ab79178 CR3: 000000003450c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000004144
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
alloc_skb include/linux/skbuff.h:1331 [inline]
nlmsg_new include/net/netlink.h:1018 [inline]
__neigh_notify+0x157/0x300 net/core/neighbour.c:3457
neigh_cleanup_and_release+0xb7/0x2a0 net/core/neighbour.c:119
neigh_periodic_work+0xaf6/0xde0 net/core/neighbour.c:959
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd30 kernel/workqueue.c:3400
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245