INFO: task syz-executor.0:24279 blocked for more than 143 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:28496 pid:24279 ppid: 17682 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6250 schedule+0xd2/0x260 kernel/sched/core.c:6323 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178 nbd_add_socket+0x166/0x810 drivers/block/nbd.c:1109 __nbd_ioctl drivers/block/nbd.c:1454 [inline] nbd_ioctl+0x38c/0xb10 drivers/block/nbd.c:1511 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: 0033:0x7f24eac8bae9 RSP: 002b:00007f24e8201188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f24ead9ef60 RCX: 00007f24eac8bae9 RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003 RBP: 00007f24eace5f6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd386cef8f R14: 00007f24e8201300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8b983b60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 1 lock held by systemd-journal/2958: 1 lock held by in:imklog/6211: #0: ffff8880192139f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by agetty/6224: #0: ffff88807bf2b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc900029252e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 1 lock held by syz-executor.0/24279: #0: ffff88801a638998 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x151/0xb10 drivers/block/nbd.c:1504 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-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: 15091 Comm: kworker/u4:10 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0x921/0x54a0 kernel/locking/lockdep.c:5001 Code: 89 c2 48 89 44 24 68 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 73 37 00 00 8b 54 24 18 4d 8b bd 50 0a 00 00 <85> d2 0f 84 a3 05 00 00 45 31 f6 48 b8 00 00 00 00 00 fc ff df 4c RSP: 0018:ffffc90004fdfa60 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: 0000000000000028 RCX: ffffffff815caaea RDX: 0000000000000002 RSI: 0000000000000008 RDI: ffffffff8fd5da00 RBP: 0000000000000004 R08: 0000000000000000 R09: ffffffff8fd5da07 R10: fffffbfff1fabb40 R11: 0000000000000000 R12: ffff88801a9727b0 R13: ffff88801a971d00 R14: ffff88801a972760 R15: 7343464613192793 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc85c9cc000 CR3: 000000006f45b000 CR4: 0000000000350ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:688 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0x12d/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: 89 c2 mov %eax,%edx 2: 48 89 44 24 68 mov %rax,0x68(%rsp) 7: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax e: fc ff df 11: 48 c1 ea 03 shr $0x3,%rdx 15: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 19: 0f 85 73 37 00 00 jne 0x3792 1f: 8b 54 24 18 mov 0x18(%rsp),%edx 23: 4d 8b bd 50 0a 00 00 mov 0xa50(%r13),%r15 * 2a: 85 d2 test %edx,%edx <-- trapping instruction 2c: 0f 84 a3 05 00 00 je 0x5d5 32: 45 31 f6 xor %r14d,%r14d 35: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 3c: fc ff df 3f: 4c rex.WR