INFO: task syz-executor.1:22865 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.1 state:D stack:28328 pid:22865 ppid: 502 flags:0x00000004 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 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: 0033:0x7f66b9043ae9 RSP: 002b:00007f66b65b9188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f66b9156f60 RCX: 00007f66b9043ae9 RDX: 0000000000000005 RSI: 000000000000ab00 RDI: 0000000000000003 RBP: 00007f66b909df6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe4b8b051f R14: 00007f66b65b9300 R15: 0000000000022000 INFO: task syz-executor.1:22866 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.1 state:D stack:28496 pid:22866 ppid: 502 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 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 nbd_ioctl+0x151/0xb10 drivers/block/nbd.c:1504 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: 0033:0x7f66b9043ae9 RSP: 002b:00007f66b6598188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f66b9157020 RCX: 00007f66b9043ae9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000006 RBP: 00007f66b909df6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe4b8b051f R14: 00007f66b6598300 R15: 0000000000022000 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 1 lock held by in:imklog/6224: #0: ffff88807b86f9f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by agetty/6450: #0: ffff88801c003098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc90002a7c2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 3 locks held by kworker/u4:7/11860: 1 lock held by syz-executor.1/22865: #0: ffff88801a8b4998 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x151/0xb10 drivers/block/nbd.c:1504 1 lock held by syz-executor.1/22866: #0: ffff88801a8b4998 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x151/0xb10 drivers/block/nbd.c:1504 1 lock held by syz-executor.1/22889: #0: ffff88801a8b4998 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x151/0xb10 drivers/block/nbd.c:1504 ============================================= 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: 2966 Comm: systemd-journal Not tainted 5.16.0-rc1-next-20211118-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:330 [inline] RIP: 0010:rcu_is_watching+0x35/0xb0 kernel/rcu/tree.c:1121 Code: 41 de 07 48 c7 c3 50 aa 03 00 83 f8 07 89 c5 77 77 48 8d 3c ed a0 08 56 8b 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 51 48 03 1c ed a0 08 56 8b 48 b8 00 00 00 00 00 fc RSP: 0000:ffffc90000dc0c98 EFLAGS: 00000802 RAX: dffffc0000000000 RBX: 000000000003aa50 RCX: ffa44a5b7aac0627 RDX: 1ffffffff16ac115 RSI: 0000000000000102 RDI: ffffffff8b5608a8 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8ff72a07 R10: fffffbfff1fee540 R11: 0000000000000000 R12: ffff88807cd15800 R13: 1ffff920001b81a8 R14: ffffffff814c66e0 R15: ffff888010c64c00 FS: 00007fdd3d9718c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fdd3b2e7000 CR3: 000000007a956000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock include/linux/rcupdate.h:689 [inline] __queue_work+0x104/0xf30 kernel/workqueue.c:1443 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1461 [inline] __run_timers.part.0+0x49f/0xa20 kernel/time/timer.c:1734 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:rcu_read_unlock_sched_notrace include/linux/rcupdate.h:810 [inline] RIP: 0010:trace_lock_acquire include/trace/events/lock.h:13 [inline] RIP: 0010:lock_acquire+0x44d/0x510 kernel/locking/lockdep.c:5608 Code: ff ff e8 85 87 a3 ff e9 59 fc ff ff 65 ff 05 1a b2 a5 7e 48 8b 05 73 f0 1f 0c e8 1e cb 05 00 85 c0 74 17 65 ff 0d 03 b2 a5 7e <0f> 85 78 fc ff ff e8 57 87 a3 ff e9 6e fc ff ff e8 9e 7b e4 07 85 RSP: 0000:ffffc9000206fbb8 EFLAGS: 00000282 RAX: 0000000000000001 RBX: 1ffff9200040df79 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8d90e7d7 R10: fffffbfff1b21cfa R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88807a947018 R15: 0000000000000000 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:354 [inline] finish_fault+0x5d3/0x9a0 mm/memory.c:4043 do_shared_fault mm/memory.c:4241 [inline] do_fault mm/memory.c:4301 [inline] handle_pte_fault mm/memory.c:4555 [inline] __handle_mm_fault+0x2674/0x5120 mm/memory.c:4690 handle_mm_fault+0x1c8/0x790 mm/memory.c:4788 do_user_addr_fault+0x489/0x11c0 arch/x86/mm/fault.c:1397 handle_page_fault arch/x86/mm/fault.c:1485 [inline] exc_page_fault+0x9e/0x180 arch/x86/mm/fault.c:1541 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:568 RIP: 0033:0x7fdd3cc7a041 Code: fc ff 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 49 48 83 fa 40 0f 87 9f 00 00 00 c5 fe 6f 06 c5 fe 6f 4c 16 e0 c5 fe 7f 07 fe 7f 4c 17 e0 c5 f8 77 c3 48 3b 15 36 54 27 00 0f 83 25 01 00 RSP: 002b:00007ffed3a7ef18 EFLAGS: 00010283 RAX: 00007fdd3b2e6fd8 RBX: 000055efff60c230 RCX: 00000000007f6f98 RDX: 0000000000000029 RSI: 000055efff60c230 RDI: 00007fdd3b2e6fd8 RBP: 0000000000000029 R08: 00000000007f7001 R09: 000055efff603120 R10: 00007ffed3a7f0c0 R11: 0000000000061248 R12: 000055efff602e80 R13: 0000000000000000 R14: 00007ffed3a7f0c8 R15: 00007fdd3b2e6f98 ---------------- Code disassembly (best guess): 0: 41 de 07 fiadds (%r15) 3: 48 c7 c3 50 aa 03 00 mov $0x3aa50,%rbx a: 83 f8 07 cmp $0x7,%eax d: 89 c5 mov %eax,%ebp f: 77 77 ja 0x88 11: 48 8d 3c ed a0 08 56 lea -0x74a9f760(,%rbp,8),%rdi 18: 8b 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 75 51 jne 0x81 30: 48 03 1c ed a0 08 56 add -0x74a9f760(,%rbp,8),%rbx 37: 8b 38: 48 rex.W 39: b8 00 00 00 00 mov $0x0,%eax 3e: 00 fc add %bh,%ah