INFO: task syz-executor.4:10426 blocked for more than 140 seconds. Not tainted 4.14.302-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28880 10426 8012 0x00000004 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_timeout+0x80a/0xe90 kernel/time/timer.c:1724 do_wait_for_common kernel/sched/completion.c:91 [inline] __wait_for_common kernel/sched/completion.c:112 [inline] wait_for_common+0x272/0x430 kernel/sched/completion.c:123 usb_start_wait_urb+0x125/0x440 drivers/usb/core/message.c:61 usb_bulk_msg+0x1f6/0x500 drivers/usb/core/message.c:252 proc_bulk+0x331/0x6d0 drivers/usb/core/devio.c:1223 usbdev_do_ioctl+0x5b0/0x2b70 drivers/usb/core/devio.c:2449 nla_parse: 69 callbacks suppressed netlink: 20 bytes leftover after parsing attributes in process `syz-executor.3'. usbdev_ioctl+0x21/0x30 drivers/usb/core/devio.c:2599 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 netlink: 20 bytes leftover after parsing attributes in process `syz-executor.3'. do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 RIP: 0033:0x7fe83e5d60a9 RSP: 002b:00007fe83cb48168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fe83e6f5f80 RCX: 00007fe83e5d60a9 netlink: 20 bytes leftover after parsing attributes in process `syz-executor.3'. RDX: 0000000020000200 RSI: 00000000c0185502 RDI: 0000000000000003 RBP: 00007fe83e631ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 netlink: 20 bytes leftover after parsing attributes in process `syz-executor.3'. R13: 00007fffe99257ff R14: 00007fe83cb48300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1533: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 1 lock held by syz-executor.5/8006: #0: (tasklist_lock){.+.+}, at: [] release_task+0x14d/0x1380 kernel/exit.c:198 ============================================= netlink: 20 bytes leftover after parsing attributes in process `syz-executor.3'. NMI backtrace for cpu 0 CPU: 0 PID: 1533 Comm: khungtaskd Not tainted 4.14.302-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4626 Comm: systemd-udevd Not tainted 4.14.302-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 task: ffff88809cb081c0 task.stack: ffff88809cb10000 RIP: 0010:mark_held_locks+0x86/0xf0 kernel/locking/lockdep.c:2846 RSP: 0018:ffff88809cb178d0 EFLAGS: 00000002 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000002 RSI: ffff88809cb08a48 RDI: ffff88809cb08a6a RBP: 0000000000000003 R08: ffffffff8b9a8108 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002 R13: ffff88809cb081c0 R14: dffffc0000000000 R15: ffff88809cb08a48 FS: 00007f839c3a98c0(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe1af89ff8 CR3: 000000009c4cf000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __trace_hardirqs_on_caller kernel/locking/lockdep.c:2875 [inline] trace_hardirqs_on_caller+0x288/0x580 kernel/locking/lockdep.c:2930 seqcount_lockdep_reader_access include/linux/seqlock.h:83 [inline] read_seqcount_begin include/linux/seqlock.h:164 [inline] __follow_mount_rcu+0x362/0x640 fs/namei.c:1354 lookup_fast+0x2ea/0xe30 fs/namei.c:1632 walk_component+0xc0/0xbc0 fs/namei.c:1821 link_path_walk+0x823/0x10a0 fs/namei.c:2154 path_lookupat+0xcb/0x780 fs/namei.c:2342 filename_lookup+0x18a/0x510 fs/namei.c:2377 SYSC_readlinkat fs/stat.c:393 [inline] SyS_readlinkat+0xa8/0x270 fs/stat.c:381 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x5e/0xd3 RIP: 0033:0x7f839b21d0ba RSP: 002b:00007ffe1af92548 EFLAGS: 00000206 ORIG_RAX: 000000000000010b RAX: ffffffffffffffda RBX: 000055ab2b902100 RCX: 00007f839b21d0ba RDX: 000055ab2b902100 RSI: 000055ab2b8fc710 RDI: 00000000ffffff9c RBP: 0000000000000064 R08: 00007f839b4d9be8 R09: 0000000000000070 R10: 0000000000000063 R11: 0000000000000206 R12: 000055ab2b8fc710 R13: 00000000ffffff9c R14: 00007ffe1af925a0 R15: 0000000000000063 Code: 83 c5 03 4d 8d bd 88 08 00 00 48 63 c3 48 8d 04 80 49 8d 34 c7 48 8d 7e 22 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 42 0f b6 04 30 <38> d0 7f 04 84 c0 75 4c 0f b6 46 22 44 89 e2 a8 03 0f 45 d5 a8 netlink: 20 bytes leftover after parsing attributes in process `syz-executor.3'.