INFO: task syz-executor.0:16990 blocked for more than 143 seconds. Not tainted 5.11.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:28552 pid:16990 ppid: 8469 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4327 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5078 schedule+0xcf/0x270 kernel/sched/core.c:5157 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1854 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion_timeout+0x15e/0x270 kernel/sched/completion.c:157 usb_start_wait_urb+0x144/0x4c0 drivers/usb/core/message.c:63 usb_bulk_msg+0x226/0x550 drivers/usb/core/message.c:387 do_proc_bulk+0x3a3/0x750 drivers/usb/core/devio.c:1231 proc_bulk drivers/usb/core/devio.c:1268 [inline] usbdev_do_ioctl drivers/usb/core/devio.c:2542 [inline] usbdev_ioctl+0x586/0x36c0 drivers/usb/core/devio.c:2708 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x465b09 RSP: 002b:00007ff166f4b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465b09 RDX: 0000000020000140 RSI: 00000000c0185502 RDI: 0000000000000003 RBP: 00000000004b069f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 0000000000a9fb1f R14: 00007ff166f4b300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1633: #0: ffffffff8bd73da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6259 1 lock held by in:imklog/8173: #0: ffff888012956370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:947 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1633 Comm: khungtaskd Not tainted 5.11.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd43/0xfa0 kernel/hung_task.c:294 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 19 Comm: kworker/1:0 Not tainted 5.11.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events ovs_dp_masks_rebalance RIP: 0010:__read_once_word_nocheck+0x0/0x10 include/asm-generic/rwonce.h:67 Code: 4c 89 f6 48 c7 c7 e0 aa be 8b e8 eb 94 a5 02 e9 60 fb ff ff e8 c1 ba 83 00 e9 cf fb ff ff cc cc cc cc cc cc cc cc cc cc cc cc <48> 8b 07 c3 66 66 2e 0f 1f 84 00 00 00 00 00 90 41 57 89 d0 41 56 RSP: 0018:ffffc90000d977f0 EFLAGS: 00000297 RAX: ffffc90000d98000 RBX: ffffc90000d97948 RCX: ffffc90000d97948 RDX: dffffc0000000000 RSI: ffffc90000d97a20 RDI: ffffc90000d97a20 RBP: ffffc90000d97a20 R08: ffffffff8e1e2852 R09: ffffffff8e1e2856 R10: 0000000000082083 R11: 0000000000000001 R12: ffffc90000d97900 R13: ffffc90000d90000 R14: ffffc90000d97950 R15: ffffc90000d97900 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f56a604a018 CR3: 0000000012cf6000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: deref_stack_reg+0xee/0x150 arch/x86/kernel/unwind_orc.c:355 unwind_next_frame+0xc3b/0x1f90 arch/x86/kernel/unwind_orc.c:531 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:401 [inline] ____kasan_kmalloc.constprop.0+0x82/0xa0 mm/kasan/common.c:429 kmalloc_array include/linux/slab.h:592 [inline] ovs_flow_masks_rebalance+0xff/0x960 net/openvswitch/flow_table.c:1116 ovs_dp_masks_rebalance+0x60/0xf0 net/openvswitch/datapath.c:2385 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296