INFO: task syz.3.357:1503 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.357 state:D stack:0 pid:1503 tgid:1502 ppid:290 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x1322/0x1df0 kernel/sched/core.c:7791 __schedule_loop kernel/sched/core.c:7872 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7887 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285 device_lock include/linux/device.h:908 [inline] usbdev_open+0x171/0x840 drivers/usb/core/devio.c:1051 chrdev_open+0x4de/0x5f0 fs/char_dev.c:414 do_dentry_open+0x978/0x1510 fs/open.c:960 vfs_open+0x86/0x230 fs/open.c:1090 do_open fs/namei.c:3774 [inline] path_openat+0x2b6c/0x34b0 fs/namei.c:3933 do_filp_open+0x1c6/0x3e0 fs/namei.c:3960 do_sys_openat2+0x12c/0x1c0 fs/open.c:1438 do_sys_open fs/open.c:1453 [inline] __do_sys_openat fs/open.c:1469 [inline] __se_sys_openat fs/open.c:1464 [inline] __x64_sys_openat+0x13a/0x170 fs/open.c:1464 x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fd55bd8d510 RSP: 002b:00007fd55cce6b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000101301 RCX: 00007fd55bd8d510 RDX: 0000000000101301 RSI: 00007fd55cce6c10 RDI: 00000000ffffff9c RBP: 00007fd55cce6c10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007fd55bfd6038 R14: 00007fd55bfd5fa0 R15: 00007ffd700b76d8 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 fee5265d319350b22cf00991634aaaf1de34201c Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xd8f/0xed0 kernel/hung_task.c:423 kthread+0x2c7/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 8820 Comm: syz.6.2705 Not tainted syzkaller #0 fee5265d319350b22cf00991634aaaf1de34201c Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:36 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:230 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:149 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:256 [inline] RIP: 0010:native_apic_msr_write+0x42/0x60 arch/x86/include/asm/apic.h:212 Code: 75 17 5d c3 cc cc cc cc cc 81 ff d0 00 00 00 74 f1 81 ff e0 00 00 00 74 e9 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 eb d4 f3 0f 1e fa 89 f6 31 d2 e8 1d 8d 9a 01 5d c3 cc cc cc RSP: 0018:ffffc90009c17980 EFLAGS: 00000046 RAX: 000000000000003e RBX: ffff8881f6e28398 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000000003e RDI: 0000000000000838 RBP: ffffc90009c17980 R08: ffff888142311300 R09: 0000000000000002 R10: 0000000000000000 R11: ffffffff8141ee60 R12: 000000000000003e R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000020 FS: 00007ff35b1e56c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee255a4198 CR3: 000000012da52000 CR4: 00000000003526b0 Call Trace: apic_write arch/x86/include/asm/apic.h:405 [inline] lapic_next_event+0x15/0x20 arch/x86/kernel/apic/apic.c:415 clockevents_program_min_delta+0x1bc/0x360 kernel/time/clockevents.c:248 clockevents_program_event+0x24d/0x350 kernel/time/clockevents.c:-1 tick_program_event+0x9b/0x120 kernel/time/tick-oneshot.c:44 __hrtimer_reprogram kernel/time/hrtimer.c:700 [inline] hrtimer_reprogram+0x341/0x3e0 kernel/time/hrtimer.c:883 hrtimer_start_range_ns+0x16da/0x2190 kernel/time/hrtimer.c:1348 hrtimer_start_expires include/linux/hrtimer.h:290 [inline] hrtimer_restart include/linux/hrtimer.h:298 [inline] common_hrtimer_rearm+0x10e/0x120 kernel/time/posix-timers.c:250 posixtimer_rearm+0x152/0x360 kernel/time/posix-timers.c:268 dequeue_signal+0x1c6/0x4f0 kernel/signal.c:700 get_signal+0x51c/0x14f0 kernel/signal.c:2813 arch_do_signal_or_restart+0x96/0x720 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x58/0xb0 kernel/entry/common.c:218 do_syscall_64+0x64/0xf0 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7ff35a38eba9 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:00007ff35b1e50e8 EFLAGS: 00000246 RAX: fffffffffffffffc RBX: 00007ff35a5d6098 RCX: 00007ff35a38eba9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007ff35a5d6098 RBP: 00007ff35a5d6090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff35a5d6128 R14: 00007ffe71f7eef0 R15: 00007ffe71f7efd8