INFO: task syz-executor.0:5409 blocked for more than 143 seconds. Not tainted 6.5.0-next-20230905-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:28464 pid:5409 ppid:5389 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0xee1/0x59f0 kernel/sched/core.c:6695 schedule+0xe7/0x1b0 kernel/sched/core.c:6771 schedule_timeout+0x27a/0x2c0 kernel/time/timer.c:2143 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3e2/0x5f0 kernel/sched/completion.c:116 __flush_workqueue+0x3e9/0x1330 kernel/workqueue.c:3195 nbd_start_device_ioctl drivers/block/nbd.c:1426 [inline] __nbd_ioctl drivers/block/nbd.c:1486 [inline] nbd_ioctl+0x308/0xc50 drivers/block/nbd.c:1526 blkdev_ioctl+0x2f9/0x770 block/ioctl.c:628 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fbceb4780e9 RSP: 002b:00007fbcec5200d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fbceb57bf60 RCX: 00007fbceb4780e9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fbceb4d2c9b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fbceb57bf60 R15: 00007ffcf75aa638 INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.5.0-next-20230905-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x299/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfac/0x1230 kernel/hung_task.c:379 kthread+0x33a/0x430 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4256 Comm: kworker/u4:9 Not tainted 6.5.0-next-20230905-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:write_comp_data+0x3c/0x90 kernel/kcov.c:236 Code: 01 00 00 49 89 f8 65 48 8b 14 25 c0 bc 03 00 a9 00 01 ff 00 74 0e 85 f6 74 59 8b 82 04 16 00 00 85 c0 74 4f 8b 82 e0 15 00 00 <83> f8 03 75 44 48 8b 82 e8 15 00 00 8b 92 e4 15 00 00 48 8b 38 48 RSP: 0018:ffffc9000e9ef920 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880b9844180 RCX: ffffffff817c53da RDX: ffff88802a315940 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffed1017308831 R13: 0000000000000001 R14: ffff8880b993d8c0 R15: ffff8880b9844188 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000561805c89680 CR3: 000000000c976000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: csd_lock_wait kernel/smp.c:300 [inline] smp_call_function_many_cond+0x4fa/0x1570 kernel/smp.c:844 on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1012 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1990 [inline] text_poke_bp_batch+0x83a/0x960 arch/x86/kernel/alternative.c:2200 text_poke_flush arch/x86/kernel/alternative.c:2391 [inline] text_poke_flush arch/x86/kernel/alternative.c:2388 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2398 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x32e/0x410 kernel/jump_label.c:829 static_key_enable_cpuslocked+0x1b5/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:830 [inline] toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:822 process_one_work+0x887/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8bb/0x1290 kernel/workqueue.c:2784 kthread+0x33a/0x430 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304