INFO: task syz-executor.4:12115 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28256 12115 8133 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 schedule_timeout+0x92d/0xfe0 kernel/time/timer.c:1794 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common+0x29c/0x470 kernel/sched/completion.c:115 usb_start_wait_urb+0x14b/0x4c0 drivers/usb/core/message.c:62 usb_bulk_msg+0x226/0x550 drivers/usb/core/message.c:253 proc_bulk+0x3de/0x860 drivers/usb/core/devio.c:1211 usbdev_do_ioctl+0x696/0x3030 drivers/usb/core/devio.c:2435 usbdev_ioctl+0x21/0x30 drivers/usb/core/devio.c:2585 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fb767932279 Code: Bad RIP value. RSP: 002b:00007fb7662a7168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fb767a44f80 RCX: 00007fb767932279 RDX: 0000000020000000 RSI: 00000000c0185502 RDI: 0000000000000003 RBP: 00007fb76798c189 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffa195cdef R14: 00007fb7662a7300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1570: #0: 0000000040fc4cbe (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7796: #0: 000000006bc5bd56 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 1 lock held by systemd-udevd/18295: #0: 000000008e126e30 (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0xfc/0x870 fs/block_dev.c:1806 2 locks held by systemd-udevd/18302: #0: 00000000ef39a97f (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x1d0/0x1480 fs/block_dev.c:1478 #1: 0000000040fc4cbe (rcu_read_lock){....}, at: trace_sched_stat_runtime include/trace/events/sched.h:428 [inline] #1: 0000000040fc4cbe (rcu_read_lock){....}, at: update_curr+0x2c3/0x870 kernel/sched/fair.c:857 1 lock held by syz-executor.0/18842: #0: 0000000085196bdb (loop_ctl_mutex){+.+.}, at: __loop_clr_fd+0x88/0xe50 drivers/block/loop.c:1080 1 lock held by syz-executor.2/18849: #0: 00000000ef39a97f (&bdev->bd_mutex){+.+.}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1839 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 18295 Comm: systemd-udevd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 RIP: 0010:__list_del_entry_valid+0xad/0xf0 lib/list_debug.c:54 Code: 02 00 75 51 49 8b 14 24 48 39 ea 0f 85 e8 51 85 04 49 8d 7d 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <75> 22 49 8b 55 08 48 39 ea 0f 85 f9 51 85 04 5d b8 01 00 00 00 41 RSP: 0018:ffff8880586877d0 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: 0000000000000001 RCX: 0000000000000000 RDX: 1ffffd400050b022 RSI: 0000000000000068 RDI: ffffea0002858110 RBP: ffffea0002a76788 R08: 0000000000000001 R09: ffffed1027fff788 R10: ffff88813fffbc43 R11: 0000000000000000 R12: ffff88813fffb828 R13: ffffea0002858108 R14: ffff88813fffb6c0 R15: dffffc0000000000 FS: 00007fc1883f68c0(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c014ad3ad4 CR3: 00000000b44d1000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_del_entry include/linux/list.h:117 [inline] list_del include/linux/list.h:125 [inline] __rmqueue_smallest mm/page_alloc.c:1985 [inline] __rmqueue mm/page_alloc.c:2475 [inline] rmqueue mm/page_alloc.c:3034 [inline] get_page_from_freelist+0x180f/0x4170 mm/page_alloc.c:3373 __alloc_pages_nodemask+0x387/0x2890 mm/page_alloc.c:4399 __alloc_pages include/linux/gfp.h:496 [inline] __alloc_pages_node include/linux/gfp.h:509 [inline] kmem_getpages mm/slab.c:1412 [inline] cache_grow_begin+0xa4/0x8a0 mm/slab.c:2682 cache_alloc_refill+0x273/0x340 mm/slab.c:3049 ____cache_alloc mm/slab.c:3132 [inline] __do_cache_alloc mm/slab.c:3354 [inline] slab_alloc mm/slab.c:3389 [inline] kmem_cache_alloc+0x346/0x370 mm/slab.c:3557 getname_flags+0xce/0x590 fs/namei.c:140 user_path_at_empty+0x2a/0x50 fs/namei.c:2609 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0x113/0x210 fs/stat.c:185 vfs_lstat include/linux/fs.h:3137 [inline] __do_sys_newlstat fs/stat.c:350 [inline] __se_sys_newlstat+0x96/0x120 fs/stat.c:344 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fc187268335 Code: 69 db 2b 00 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 83 ff 01 48 89 f0 77 30 48 89 c7 48 89 d6 b8 06 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 03 f3 c3 90 48 8b 15 31 db 2b 00 f7 d8 64 89 RSP: 002b:00007fff17daeee8 EFLAGS: 00000246 ORIG_RAX: 0000000000000006 RAX: ffffffffffffffda RBX: 0000564aa30a1e21 RCX: 00007fc187268335 RDX: 00007fff17daef90 RSI: 00007fff17daef90 RDI: 00007fff17daeef0 RBP: 00007fff17daf060 R08: 000000000000feff R09: 0000000000000168 R10: 0000000000000001 R11: 0000000000000246 R12: 00007fff17daf070 R13: 00007fff17daef68 R14: 0000000000000018 R15: 0000564aa308d250