INFO: task kworker/1:0H:25 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:0H state:D stack:26152 pid:25 tgid:25 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: kblockd blk_mq_requeue_work Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 wait_for_reconnect drivers/block/nbd.c:1104 [inline] nbd_handle_cmd drivers/block/nbd.c:1146 [inline] nbd_queue_rq+0x662/0xf10 drivers/block/nbd.c:1204 blk_mq_dispatch_rq_list+0x4bd/0x1900 block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xda4/0x1570 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0xd7/0x190 block/blk-mq-sched.c:329 blk_mq_run_hw_queue+0x348/0x4f0 block/blk-mq.c:2358 blk_mq_run_hw_queues+0x33e/0x430 block/blk-mq.c:2407 blk_mq_requeue_work+0x717/0x760 block/blk-mq.c:1574 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline] watchdog+0xf93/0xfe0 kernel/hung_task.c:491 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__schedule+0x84e/0x4cc0 kernel/sched/core.c:6951 Code: 8b 5c 24 58 74 08 48 89 df e8 2e 9f a8 f6 48 8b 44 24 08 48 89 03 4c 8b bc 24 a0 00 00 00 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 <48> 8b 1c 24 74 08 4c 89 ff e8 14 9e a8 f6 49 ff 07 4c 8d bb 28 0c RSP: 0018:ffffc90000197bc0 EFLAGS: 00000046 RAX: 1ffff110039d5c30 RBX: ffff8880b873aa88 RCX: ffffffff8b7a75cb RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff88801ceada00 RBP: ffffc90000197dd0 R08: ffff88801ceada07 R09: 1ffff110039d5b40 R10: dffffc0000000000 R11: ffffed10039d5b41 R12: dffffc0000000000 R13: 0000000000000000 R14: ffff88801ceada00 R15: ffff88801ceae180 FS: 0000000000000000(0000) GS:ffff888125d1b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f37f19f84c0 CR3: 000000000df36000 CR4: 00000000003526f0 Call Trace: schedule_idle+0x52/0x90 kernel/sched/core.c:7084 do_idle+0x4ad/0x510 kernel/sched/idle.c:358 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147