INFO: task syz-executor.2:6558 blocked for more than 143 seconds. Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:22944 pid: 6558 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4987 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6268 schedule+0xd2/0x260 kernel/sched/core.c:6341 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178 __loop_clr_fd+0x1ae/0x1070 drivers/block/loop.c:1122 lo_release+0x1ac/0x1f0 drivers/block/loop.c:1761 blkdev_put_whole block/bdev.c:694 [inline] blkdev_put+0x2fb/0x9e0 block/bdev.c:956 deactivate_locked_super+0x94/0x160 fs/super.c:335 deactivate_super+0xad/0xd0 fs/super.c:366 cleanup_mnt+0x3a2/0x540 fs/namespace.c:1137 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fa9ed96bf57 RSP: 002b:00007ffe666d8e88 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fa9ed96bf57 RDX: 00007ffe666d8f5c RSI: 000000000000000a RDI: 00007ffe666d8f50 RBP: 00007ffe666d8f50 R08: 00000000ffffffff R09: 00007ffe666d8d20 R10: 0000555556d28903 R11: 0000000000000246 R12: 00007fa9ed9c4105 R13: 00007ffe666da010 R14: 0000555556d28810 R15: 00007ffe666da050 INFO: task systemd-udevd:30460 blocked for more than 143 seconds. Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:systemd-udevd state:D stack:26888 pid:30460 ppid: 2973 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:4987 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6268 schedule+0xd2/0x260 kernel/sched/core.c:6341 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6400 __mutex_lock_common kernel/locking/mutex.c:680 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740 blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 blkdev_get_by_dev+0x6b/0x80 block/bdev.c:859 blkdev_open+0x154/0x2e0 block/fops.c:501 do_dentry_open+0x4c8/0x1250 fs/open.c:822 do_open fs/namei.c:3426 [inline] path_openat+0x1cad/0x2750 fs/namei.c:3559 do_filp_open+0x1aa/0x400 fs/namei.c:3586 do_sys_openat2+0x16d/0x4d0 fs/open.c:1212 do_sys_open fs/open.c:1228 [inline] __do_sys_open fs/open.c:1236 [inline] __se_sys_open fs/open.c:1232 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1232 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f651e20b840 RSP: 002b:00007ffc66d17278 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000055923e596a20 RCX: 00007f651e20b840 RDX: 000055923caf4fe3 RSI: 00000000000a0800 RDI: 000055923e590940 RBP: 00007ffc66d173f0 R08: 000055923caf4670 R09: 0000000000000010 R10: 000055923caf4d0c R11: 0000000000000246 R12: 00007ffc66d17340 R13: 000055923e595d10 R14: 0000000000000003 R15: 000000000000000e Showing all locks held in the system: 1 lock held by khungtaskd/26: #0: ffffffff8bb83ba0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 2 locks held by syz-executor.2/6558: #0: ffff88801a8d3918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x97/0x9e0 block/bdev.c:914 #1: ffff88801a51f360 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x7a/0x1070 drivers/block/loop.c:1106 1 lock held by systemd-udevd/30460: #0: ffff88801a8d3918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 26 Comm: khungtaskd Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 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:254 [inline] watchdog+0xcb7/0xed0 kernel/hung_task.c:339 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1077 Comm: kworker/u4:6 Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__this_cpu_preempt_check+0x0/0x20 lib/smp_processor_id.c:65 Code: e8 ba d7 cc ff eb a2 0f 1f 00 0f 1f 44 00 00 48 c7 c6 20 b6 04 8a 48 c7 c7 60 b6 04 8a e9 78 fe ff ff 0f 1f 84 00 00 00 00 00 <55> 48 89 fd 0f 1f 44 00 00 48 89 ee 5d 48 c7 c7 a0 b6 04 8a e9 57 RSP: 0018:ffffc90004ee7b70 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff89ac10c0 RBP: ffffffff8bb83ae0 R08: 0000000000000000 R09: ffffffff8d90e7d7 R10: fffffbfff1b21cfa R11: 0000000000000000 R12: ffff88801c360000 R13: 00000000ffffffff R14: 00000000ffffffff R15: 0000000000000220 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f428264c000 CR3: 0000000021f48000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:433 [inline] lock_is_held_type+0x63/0x140 kernel/locking/lockdep.c:5679 lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125 trace_lock_release include/trace/events/lock.h:58 [inline] lock_release+0x522/0x720 kernel/locking/lockdep.c:5648 rcu_lock_release include/linux/rcupdate.h:273 [inline] rcu_read_unlock include/linux/rcupdate.h:721 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline] batadv_nc_worker+0x86b/0xfa0 net/batman-adv/network-coding.c:723 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: e8 ba d7 cc ff callq 0xffccd7bf 5: eb a2 jmp 0xffffffa9 7: 0f 1f 00 nopl (%rax) a: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) f: 48 c7 c6 20 b6 04 8a mov $0xffffffff8a04b620,%rsi 16: 48 c7 c7 60 b6 04 8a mov $0xffffffff8a04b660,%rdi 1d: e9 78 fe ff ff jmpq 0xfffffe9a 22: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1) 29: 00 * 2a: 55 push %rbp <-- trapping instruction 2b: 48 89 fd mov %rdi,%rbp 2e: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 33: 48 89 ee mov %rbp,%rsi 36: 5d pop %rbp 37: 48 c7 c7 a0 b6 04 8a mov $0xffffffff8a04b6a0,%rdi 3e: e9 .byte 0xe9 3f: 57 push %rdi