INFO: task syz-executor.2:16332 blocked for more than 143 seconds. Not tainted 5.16.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:23920 pid:16332 ppid: 6543 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xb72/0x1460 kernel/sched/core.c:6253 schedule+0x12b/0x1f0 kernel/sched/core.c:6326 blk_mq_freeze_queue_wait+0x105/0x190 block/blk-mq.c:178 __loop_clr_fd+0x1c6/0x9b0 drivers/block/loop.c:1122 loop_clr_fd drivers/block/loop.c:1237 [inline] lo_ioctl+0x107b/0x1f40 drivers/block/loop.c:1562 blkdev_ioctl+0x3ac/0x790 block/ioctl.c:609 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f24194af8a7 RSP: 002b:00007f2416a24fa8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f24194af8a7 RDX: 0000000000000000 RSI: 0000000000004c01 RDI: 0000000000000005 RBP: 00007f2416a256bc R08: 00007f2416a25040 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff R13: 000000000000000d R14: 00007f2416a25000 R15: 0000000020013500 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8cb1dc00 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by systemd-udevd/2970: #0: ffff88801b2b7918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0xfc/0xb80 block/bdev.c:819 #1: ffff88801b2b3360 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_open+0x68/0x100 drivers/block/loop.c:1733 1 lock held by in:imklog/6204: #0: ffff88807169eaf0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:990 1 lock held by syz-executor.2/16332: #0: ffff88801b2b3360 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x6d/0x9b0 drivers/block/loop.c:1106 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.16.0-rc1-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+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc82/0xcd0 kernel/hung_task.c:295 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 986 Comm: kworker/u4:4 Not tainted 5.16.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_dat_purge RIP: 0010:check_preemption_disabled+0x3/0x1c0 lib/smp_processor_id.c:13 Code: cc cc cc cc cc cc cc 0f 1f 44 00 00 48 c7 c7 20 4a d5 8a 48 c7 c6 60 4a d5 8a eb 0b 66 2e 0f 1f 84 00 00 00 00 00 90 55 41 57 <41> 56 41 55 41 54 53 48 83 ec 10 49 89 f6 49 89 ff 65 48 8b 04 25 RSP: 0018:ffffc90004adf940 EFLAGS: 00000046 RAX: 0000000000000002 RBX: 0000000000000000 RCX: 0000000080000202 RDX: 0000000000000000 RSI: ffffffff8a6f1840 RDI: ffffffff8ad54aa0 RBP: 0000000000000002 R08: dffffc0000000000 R09: fffffbfff1bfd13e R10: fffffbfff1bfd13e R11: 0000000000000000 R12: 0000000000000246 R13: ffff88801cb78000 R14: 00000000ffffffff R15: ffffffff8cb1db60 FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe6738ca000 CR3: 000000000c88e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:438 [inline] lock_is_held_type+0x109/0x190 kernel/locking/lockdep.c:5681 lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x89/0x130 kernel/rcu/update.c:125 trace_lock_acquire+0x59/0x190 include/trace/events/lock.h:13 lock_acquire+0xa5/0x4d0 kernel/locking/lockdep.c:5608 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:354 [inline] __batadv_dat_purge net/batman-adv/distributed-arp-table.c:175 [inline] batadv_dat_purge+0xe7/0x500 net/batman-adv/distributed-arp-table.c:206 process_one_work+0x853/0x1140 kernel/workqueue.c:2298 worker_thread+0xac1/0x1320 kernel/workqueue.c:2445 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 ---------------- Code disassembly (best guess): 0: cc int3 1: cc int3 2: cc int3 3: cc int3 4: cc int3 5: cc int3 6: cc int3 7: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) c: 48 c7 c7 20 4a d5 8a mov $0xffffffff8ad54a20,%rdi 13: 48 c7 c6 60 4a d5 8a mov $0xffffffff8ad54a60,%rsi 1a: eb 0b jmp 0x27 1c: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 23: 00 00 00 26: 90 nop 27: 55 push %rbp 28: 41 57 push %r15 * 2a: 41 56 push %r14 <-- trapping instruction 2c: 41 55 push %r13 2e: 41 54 push %r12 30: 53 push %rbx 31: 48 83 ec 10 sub $0x10,%rsp 35: 49 89 f6 mov %rsi,%r14 38: 49 89 ff mov %rdi,%r15 3b: 65 gs 3c: 48 rex.W 3d: 8b .byte 0x8b 3e: 04 25 add $0x25,%al