INFO: task syz.3.11053:11165 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.11053 state:D stack:28112 pid:11165 tgid:11162 ppid:9466 task_flags:0x400040 flags:0x00004004 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_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 device_lock include/linux/device.h:911 [inline] usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 chrdev_open+0x4cc/0x5e0 fs/char_dev.c:414 do_dentry_open+0x950/0x13f0 fs/open.c:965 vfs_open+0x3b/0x340 fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4046 do_filp_open+0x1fa/0x410 fs/namei.c:4073 do_sys_openat2+0x121/0x1c0 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1461 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3bb658d550 RSP: 002b:00007f3bb73afb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3bb658d550 RDX: 0000000000000000 RSI: 00007f3bb73afc10 RDI: 00000000ffffff9c RBP: 00007f3bb73afc10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007f3bb67b6128 R14: 00007f3bb67b6090 R15: 00007ffdad60fc38 INFO: lockdep is turned off. NMI backtrace for cpu 1 CPU: 1 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:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x47c/0x820 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 14926 Comm: syz.8.12347 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__kernel_text_address+0x2e/0x40 kernel/extable.c:92 Code: 53 48 89 fb e8 43 00 00 00 85 c0 0f 95 c0 48 81 fb 00 e0 4d 91 0f 93 c1 48 81 fb 60 35 64 91 0f 92 c2 20 ca 08 c2 0f b6 c2 5b bd 5d fb 09 cc 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 RSP: 0018:ffffc90003b36620 EFLAGS: 00000202 RAX: 0000000000000001 RBX: ffffc90003b36690 RCX: 6a69546da7ad8b00 RDX: ffffc90003b36601 RSI: ffffffff8c04e5e0 RDI: ffffffff82243fce RBP: ffffc90003b366d0 R08: ffffc90003b36770 R09: 0000000000000000 R10: ffffc90003b36698 R11: fffff52000766cd5 R12: ffff88807c5d9e00 R13: ffff88807504d200 R14: dffffc0000000000 R15: 1ffff92000766cd2 FS: 00007f21b95216c0(0000) GS:ffff8881257c4000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f76d2e7af98 CR3: 0000000039fcc000 CR4: 00000000003526f0 Call Trace: unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x21c/0x3a0 mm/slub.c:4396 kmalloc_noprof include/linux/slab.h:909 [inline] slab_free_hook mm/slub.c:2369 [inline] slab_free mm/slub.c:4680 [inline] kmem_cache_free+0x166/0x400 mm/slub.c:4782 blk_update_request+0x57e/0xe60 block/blk-mq.c:989 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1151 >::end_ok rust/kernel/block/mq/request.rs:129 [inline] ::queue_rq drivers/block/rnull.rs:69 [inline] >::queue_rq_callback+0x1b6/0x2a0 rust/kernel/block/mq/operations.rs:94 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+0x404/0x4f0 block/blk-mq.c:2358 blk_mq_dispatch_list+0xd0c/0xe00 include/linux/spinlock.h:-1 blk_mq_flush_plug_list+0x469/0x550 block/blk-mq.c:2967 __blk_flush_plug+0x3d3/0x4b0 block/blk-core.c:1220 blk_finish_plug+0x5e/0x90 block/blk-core.c:1247 blkdev_writepages+0x10e/0x170 block/fops.c:484 do_writepages+0x32e/0x550 mm/page-writeback.c:2634 filemap_fdatawrite_wbc mm/filemap.c:386 [inline] __filemap_fdatawrite_range mm/filemap.c:419 [inline] file_write_and_wait_range+0x23e/0x340 mm/filemap.c:794 blkdev_fsync+0x74/0xd0 block/fops.c:615 generic_write_sync+0x1b3/0x290 include/linux/fs.h:3036 blkdev_write_iter+0x5fa/0x710 block/fops.c:800 iter_file_splice_write+0x975/0x10e0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x101/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5a5/0xcc0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x181/0x270 fs/splice.c:1230 do_sendfile+0x4da/0x7e0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1431 [inline] __se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f21b878ebe9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f21b9521038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f21b89b5fa0 RCX: 00007f21b878ebe9 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000004 RBP: 00007f21b8811e19 R08: 0000000000000000 R09: 0000000000000000 R10: 000000007ffff000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f21b89b6038 R14: 00007f21b89b5fa0 R15: 00007ffe60794d88