INFO: task syz-executor326:3645 blocked for more than 143 seconds. Not tainted 6.0.0-rc5-syzkaller-00094-ga335366bad13 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor326 state:D stack:28176 pid: 3645 ppid: 3635 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5182 [inline] __schedule+0xadf/0x52b0 kernel/sched/core.c:6494 schedule+0xda/0x1b0 kernel/sched/core.c:6570 blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:180 nbd_add_socket+0x166/0x810 drivers/block/nbd.c:1123 __nbd_ioctl drivers/block/nbd.c:1464 [inline] nbd_ioctl+0x4ab/0xbd0 drivers/block/nbd.c:1521 blkdev_ioctl+0x36e/0x800 block/ioctl.c:614 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856 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+0x63/0xcd RIP: 0033:0x7fa9b8376399 RSP: 002b:00007ffc31bc5218 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000000771ae RCX: 00007fa9b8376399 RDX: 0000000000000004 RSI: 000000000000ab00 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffc31bc53b8 R09: 00007ffc31bc53b8 R10: 00007ffc31bc4c90 R11: 0000000000000246 R12: 00007ffc31bc522c R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8bf85db0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 1 lock held by rcu_tasks_trace/13: #0: ffffffff8bf85ab0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 1 lock held by khungtaskd/28: #0: ffffffff8bf86900 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6492 2 locks held by getty/3293: #0: ffff88814ab0c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc90001c282f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef0/0x13e0 drivers/tty/n_tty.c:2177 1 lock held by syz-executor326/3645: #0: ffff8881472a0198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x151/0xbd0 drivers/block/nbd.c:1514 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.0.0-rc5-syzkaller-00094-ga335366bad13 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x46/0x14f lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x206/0x250 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xc18/0xf50 kernel/hung_task.c:369 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11 Comm: kworker/u4:1 Not tainted 6.0.0-rc5-syzkaller-00094-ga335366bad13 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:write_comp_data+0x3c/0x90 kernel/kcov.c:229 Code: 01 00 00 49 89 f8 65 48 8b 14 25 80 6f 02 00 a9 00 01 ff 00 74 0e 85 f6 74 59 8b 82 bc 15 00 00 85 c0 74 4f 8b 82 98 15 00 00 <83> f8 03 75 44 48 8b 82 a0 15 00 00 8b 92 9c 15 00 00 48 8b 38 48 RSP: 0018:ffffc9000031f9c0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffc9000031fa78 RCX: ffffffff8425994c RDX: ffff8880121da040 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000003 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000044 R13: 000000000000000f R14: 1ffff92000063f49 R15: ffffffff89e6ac8a FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005593ad02d600 CR3: 000000000bc8e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: insn_get_sib arch/x86/lib/insn.c:428 [inline] insn_get_sib+0x17c/0x330 arch/x86/lib/insn.c:412 insn_get_displacement+0x346/0x6c0 arch/x86/lib/insn.c:464 insn_get_immediate arch/x86/lib/insn.c:632 [inline] insn_get_length arch/x86/lib/insn.c:707 [inline] insn_decode+0x35b/0x3b0 arch/x86/lib/insn.c:747 text_poke_loc_init+0xa6/0x450 arch/x86/kernel/alternative.c:1580 arch_jump_label_transform_queue+0x94/0x100 arch/x86/kernel/jump_label.c:138 __jump_label_update+0x12e/0x410 kernel/jump_label.c:447 jump_label_update+0x32f/0x410 kernel/jump_label.c:801 static_key_disable_cpuslocked+0x152/0x1b0 kernel/jump_label.c:207 static_key_disable+0x16/0x20 kernel/jump_label.c:215 toggle_allocation_gate mm/kfence/core.c:825 [inline] toggle_allocation_gate+0x183/0x390 mm/kfence/core.c:803 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306