INFO: task syz-executor.4:24131 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.4 state:D stack:28256 pid:24131 ppid: 16388 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6253 schedule+0xd2/0x260 kernel/sched/core.c:6326 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178 loop_set_status+0x440/0x930 drivers/block/loop.c:1264 loop_set_status_old+0x148/0x1b0 drivers/block/loop.c:1396 lo_ioctl+0x3e9/0x17c0 drivers/block/loop.c:1566 blkdev_ioctl+0x37a/0x800 block/ioctl.c:609 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 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: 0033:0x7f4af1854ae9 RSP: 002b:00007f4aeed88188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f4af19680e0 RCX: 00007f4af1854ae9 RDX: 00000000200000c0 RSI: 0000000000004c02 RDI: 0000000000000004 RBP: 00007f4af18aef6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffebbb6991f R14: 00007f4aeed88300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8bb83a60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 2 locks held by systemd-udevd/2975: #0: ffff88801ad01918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev.part.0+0x9b/0xb50 block/bdev.c:819 #1: ffff88801acf5360 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_open+0x75/0x120 drivers/block/loop.c:1733 1 lock held by in:imklog/6226: 2 locks held by agetty/6237: #0: ffff88807a948098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc900030a32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 1 lock held by syz-executor.4/24131: #0: ffff88801acf5360 (&lo->lo_mutex){+.+.}-{3:3}, at: loop_set_status+0x2a/0x930 drivers/block/loop.c:1248 ============================================= 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+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 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+0xc1d/0xf50 kernel/hung_task.c:295 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 14169 Comm: kworker/u4:10 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_iv_send_outstanding_bat_ogm_packet RIP: 0010:rcu_preempt_read_enter kernel/rcu/tree_plugin.h:375 [inline] RIP: 0010:__rcu_read_lock+0x67/0xf0 kernel/rcu/tree_plugin.h:398 Code: 48 8b 2c 25 40 70 02 00 48 8d bd 3c 04 00 00 8b 9b 3c 04 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c3 01 83 c0 03 38 d0 7c 04 84 d2 75 58 48 b8 RSP: 0018:ffffc900027ffb80 EFLAGS: 00000213 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff8880193a0480 RDI: ffff8880218c3e3c RBP: ffff8880218c3a00 R08: 0000000000000120 R09: 0000000000000000 R10: ffffffff88e90036 R11: 0000000000000000 R12: ffff888011a8d094 R13: dffffc0000000000 R14: ffff88803b434c80 R15: 0000000000000120 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f998316d070 CR3: 000000006f4f7000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: rcu_read_lock include/linux/rcupdate.h:686 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:755 [inline] batadv_iv_ogm_schedule_buff+0x5ad/0x1430 net/batman-adv/bat_iv_ogm.c:826 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:869 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:862 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x740/0x8e0 net/batman-adv/bat_iv_ogm.c:1713 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: 48 8b 2c 25 40 70 02 mov 0x27040,%rbp 7: 00 8: 48 8d bd 3c 04 00 00 lea 0x43c(%rbp),%rdi f: 8b 9b 3c 04 00 00 mov 0x43c(%rbx),%ebx 15: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1c: fc ff df 1f: 48 89 fa mov %rdi,%rdx 22: 48 c1 ea 03 shr $0x3,%rdx 26: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx * 2a: 48 89 f8 mov %rdi,%rax <-- trapping instruction 2d: 83 e0 07 and $0x7,%eax 30: 83 c3 01 add $0x1,%ebx 33: 83 c0 03 add $0x3,%eax 36: 38 d0 cmp %dl,%al 38: 7c 04 jl 0x3e 3a: 84 d2 test %dl,%dl 3c: 75 58 jne 0x96 3e: 48 rex.W 3f: b8 .byte 0xb8