INFO: task syz-executor.4:16655 blocked for more than 140 seconds. Not tainted 4.14.175-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D27888 16655 6360 0x80000004 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893 lo_ioctl+0x87/0x1c40 drivers/block/loop.c:1414 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x91d/0x17d0 block/ioctl.c:594 ioctl_by_bdev+0xa0/0x110 fs/block_dev.c:2066 udf_get_last_session+0x7c/0xd0 fs/udf/lowlevel.c:37 udf_fill_super+0x10f9/0x14f6 fs/udf/super.c:2146 mount_bdev+0x2bc/0x370 fs/super.c:1134 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x3c9/0x24f0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c879 RSP: 002b:00007fbf5bf30c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fbf5bf316d4 RCX: 000000000045c879 RDX: 00000000200003c0 RSI: 0000000020000380 RDI: 0000000020000340 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000749 R14: 00000000004ca13a R15: 000000000076bf0c INFO: task syz-executor.4:16661 blocked for more than 140 seconds. Not tainted 4.14.175-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28768 16661 6360 0x00000004 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3428 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline] rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309 call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94 __down_read arch/x86/include/asm/rwsem.h:66 [inline] down_read+0x45/0xa0 kernel/locking/rwsem.c:26 __get_super.part.0+0x1c6/0x280 fs/super.c:678 __get_super include/linux/spinlock.h:317 [inline] get_super+0x2b/0x50 fs/super.c:707 fsync_bdev+0x14/0xd0 fs/block_dev.c:495 invalidate_partition+0x31/0x60 block/genhd.c:1506 drop_partitions block/partition-generic.c:442 [inline] rescan_partitions+0xde/0x850 block/partition-generic.c:515 __blkdev_reread_part+0x157/0x1e0 block/ioctl.c:173 blkdev_reread_part+0x23/0x40 block/ioctl.c:193 loop_reread_partitions+0x72/0x80 drivers/block/loop.c:624 loop_clr_fd+0x839/0xad0 drivers/block/loop.c:1078 lo_ioctl+0x8a5/0x1c40 drivers/block/loop.c:1424 __blkdev_driver_ioctl block/ioctl.c:297 [inline] blkdev_ioctl+0x91d/0x17d0 block/ioctl.c:594 block_ioctl+0xd9/0x120 fs/block_dev.c:1881 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xfe0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c6e7 RSP: 002b:00007fbf5bf0f9d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 000000000045c6e7 RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000007 RBP: 0000000000000009 R08: 0000000000000000 R09: 000000000000000c R10: 0000000000000064 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000c1b R14: 00000000004c1935 R15: 000000000076bfac INFO: task syz-executor.4:16685 blocked for more than 140 seconds. Not tainted 4.14.175-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28848 16685 6360 0x00000004 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893 __blkdev_get+0x131/0x10d0 fs/block_dev.c:1457 blkdev_get+0x429/0x8a0 fs/block_dev.c:1612 blkdev_get_by_path+0x8e/0xf0 fs/block_dev.c:1690 mount_bdev+0x4c/0x370 fs/super.c:1092 mount_fs+0x92/0x2a0 fs/super.c:1237 vfs_kern_mount.part.0+0x5b/0x3c0 fs/namespace.c:1046 vfs_kern_mount fs/namespace.c:1036 [inline] do_new_mount fs/namespace.c:2549 [inline] do_mount+0x3c9/0x24f0 fs/namespace.c:2879 SYSC_mount fs/namespace.c:3095 [inline] SyS_mount+0xa8/0x120 fs/namespace.c:3072 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x45c879 RSP: 002b:00007fbf5beeec78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fbf5beef6d4 RCX: 000000000045c879 RDX: 00000000200003c0 RSI: 0000000020000380 RDI: 0000000020000340 RBP: 000000000076c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000749 R14: 00000000004ca13a R15: 000000000076c04c INFO: task syz-executor.4:16686 blocked for more than 140 seconds. Not tainted 4.14.175-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28824 16686 6360 0x00000004 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893 __blkdev_get+0x131/0x10d0 fs/block_dev.c:1457 blkdev_get+0x84/0x8a0 fs/block_dev.c:1612 blkdev_open+0x1cc/0x250 fs/block_dev.c:1770 do_dentry_open+0x732/0xe90 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x8ca/0x3c50 fs/namei.c:3569 do_filp_open+0x18e/0x250 fs/namei.c:3603 do_sys_open+0x29d/0x3f0 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x416611 RSP: 002b:00007fbf5becd9d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007fbf5bece6d4 RCX: 0000000000416611 RDX: 00007fbf5becdbba RSI: 0000000000000002 RDI: 00007fbf5becdbb0 RBP: 000000000076c0e0 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000075 R11: 0000000000000293 R12: 00000000ffffffff R13: 0000000000000c1b R14: 00000000004c1935 R15: 000000000076c0ec INFO: task systemd-udevd:16648 blocked for more than 140 seconds. Not tainted 4.14.175-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D28560 16648 3644 0x00000104 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x73c/0x1470 kernel/locking/mutex.c:893 __blkdev_get+0x131/0x10d0 fs/block_dev.c:1457 blkdev_get+0x84/0x8a0 fs/block_dev.c:1612 blkdev_open+0x1cc/0x250 fs/block_dev.c:1770 do_dentry_open+0x732/0xe90 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x8ca/0x3c50 fs/namei.c:3569 do_filp_open+0x18e/0x250 fs/namei.c:3603 do_sys_open+0x29d/0x3f0 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x7f31a7c5d840 RSP: 002b:00007fff9e850878 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000056532717ce40 RCX: 00007f31a7c5d840 RDX: 00005653251effe3 RSI: 00000000000a0800 RDI: 0000565327180840 RBP: 00007fff9e8509f0 R08: 00005653251ef670 R09: 0000000000000010 R10: 00005653251efd0c R11: 0000000000000246 R12: 00007fff9e850940 R13: 0000565327174000 R14: 0000000000000003 R15: 000000000000000e Showing all locks held in the system: 1 lock held by khungtaskd/1057: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4544 1 lock held by in:imklog/6017: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xa6/0xc0 fs/file.c:769 2 locks held by syz-executor.4/16655: #0: (&type->s_umount_key#70/1){+.+.}, at: [] alloc_super fs/super.c:251 [inline] #0: (&type->s_umount_key#70/1){+.+.}, at: [] sget_userns+0x556/0xc30 fs/super.c:516 #1: (&lo->lo_ctl_mutex/1){+.+.}, at: [] lo_ioctl+0x87/0x1c40 drivers/block/loop.c:1414 3 locks held by syz-executor.4/16661: #0: (&lo->lo_ctl_mutex/1){+.+.}, at: [] lo_ioctl+0x87/0x1c40 drivers/block/loop.c:1414 #1: (&bdev->bd_mutex){+.+.}, at: [] blkdev_reread_part+0x1b/0x40 block/ioctl.c:192 #2: (&type->s_umount_key#71){.+.+}, at: [] __get_super.part.0+0x1c6/0x280 fs/super.c:678 1 lock held by syz-executor.4/16685: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x131/0x10d0 fs/block_dev.c:1457 1 lock held by syz-executor.4/16686: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x131/0x10d0 fs/block_dev.c:1457 1 lock held by systemd-udevd/16648: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x131/0x10d0 fs/block_dev.c:1457 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1057 Comm: khungtaskd Not tainted 4.14.175-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x13e/0x194 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x139/0x17e 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+0x5e2/0xb80 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: kworker/u4:2 Not tainted 4.14.175-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker task: ffff8880a9ab8080 task.stack: ffff8880a9ac0000 RIP: 0010:trace_hardirqs_on_caller+0x2e6/0x590 kernel/locking/lockdep.c:2915 RSP: 0018:ffff8880a9ac7c68 EFLAGS: 00000046 RAX: 0000000000000082 RBX: ffffffff8a587b00 RCX: 1ffffffff10279a4 RDX: dffffc0000000000 RSI: 0000000000000000 RDI: ffff8880a9ab88c8 RBP: ffffffff813730e4 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 R13: ffffffff86283c90 R14: ffff88805442d400 R15: ffff88805442de78 FS: 0000000000000000(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee5eb5e000 CR3: 000000008a9af000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __local_bh_enable_ip+0x94/0x190 kernel/softirq.c:190 spin_unlock_bh include/linux/spinlock.h:362 [inline] batadv_nc_purge_paths+0x257/0x360 net/batman-adv/network-coding.c:479 batadv_nc_worker+0x238/0x6d0 net/batman-adv/network-coding.c:727 process_one_work+0x813/0x1540 kernel/workqueue.c:2116 worker_thread+0x5d1/0x1070 kernel/workqueue.c:2250 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: c1 e8 03 80 3c 10 00 0f 85 7b 02 00 00 48 83 3d d0 91 8b 06 00 0f 84 57 02 00 00 9c 58 0f 1f 44 00 00 f6 c4 02 0f 85 1d 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 89 da 83 e3 07 48 c1 ea 03 83