INFO: task syz.5.17:416 blocked for more than 122 seconds. Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.17 state:D stack:0 pid:416 tgid:416 ppid:374 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+0x4db/0x5f0 fs/char_dev.c:414 do_dentry_open+0x97b/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: 0033:0x7f51dd38d451 RSP: 002b:00007ffca4e32dc0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f51dd38d451 RDX: 0000000000000002 RSI: 00007ffca4e32e60 RDI: 00000000ffffff9c RBP: 00007ffca4e32e60 R08: 000000000000001f R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: cccccccccccccccd R13: 00007f51dd5b5fa0 R14: 00007f51dd5b5fa0 R15: 0000000000000003 INFO: task syz.3.20:417 blocked for more than 123 seconds. Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.20 state:D stack:0 pid:417 tgid:417 ppid:379 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+0x4db/0x5f0 fs/char_dev.c:414 do_dentry_open+0x97b/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: 0033:0x7f997bf8d451 RSP: 002b:00007ffd166213f0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f997bf8d451 RDX: 0000000000000002 RSI: 00007ffd16621490 RDI: 00000000ffffff9c RBP: 00007ffd16621490 R08: 000000000000000f R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: cccccccccccccccd R13: 00007f997c1b5fa0 R14: 00007f997c1b5fa0 R15: 0000000000000003 INFO: task syz.2.19:424 blocked for more than 123 seconds. Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.19 state:D stack:0 pid:424 tgid:424 ppid:377 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+0x4db/0x5f0 fs/char_dev.c:414 do_dentry_open+0x97b/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: 0033:0x7fdca958d451 RSP: 002b:00007ffc1a16ce70 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fdca958d451 RDX: 0000000000000002 RSI: 00007ffc1a16cf10 RDI: 00000000ffffff9c RBP: 00007ffc1a16cf10 R08: 000000000000000f R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: cccccccccccccccd R13: 00007fdca97b5fa0 R14: 00007fdca97b5fa0 R15: 0000000000000003 INFO: task syz.1.18:425 blocked for more than 123 seconds. Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.18 state:D stack:0 pid:425 tgid:425 ppid:378 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+0x4db/0x5f0 fs/char_dev.c:414 do_dentry_open+0x97b/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: 0033:0x7f83f478d451 RSP: 002b:00007ffe3812c720 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f83f478d451 RDX: 0000000000000002 RSI: 00007ffe3812c7c0 RDI: 00000000ffffff9c RBP: 00007ffe3812c7c0 R08: 000000000000001f R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: cccccccccccccccd R13: 00007f83f49b5fa0 R14: 00007f83f49b5fa0 R15: 0000000000000003 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 d02c7cfa86e34ad1734bbfdc1f5f1c3ce9be47fc Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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+0x2ca/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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 d02c7cfa86e34ad1734bbfdc1f5f1c3ce9be47fc Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:pv_native_safe_halt+0x17/0x20 arch/x86/kernel/paravirt.c:106 Code: cc cc cc b8 99 30 8f 47 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 83 71 40 00 f3 0f 1e fa 55 48 89 e5 fb f4 <5d> c3 cc cc cc cc cc cc cc b8 00 00 00 00 90 90 90 90 90 90 90 90 RSP: 0018:ffffc900001a7e00 EFLAGS: 000002c6 RAX: ffff8881f6f00000 RBX: ffff888103669300 RCX: ffffffff8586e09e RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000e1ed7c RBP: ffffc900001a7e00 R08: ffff8881f6f39733 R09: 1ffff1103ede72e6 R10: dffffc0000000000 R11: ffffed103ede72e7 R12: 1ffff110206cd260 R13: 0000000000000001 R14: 0000000000000000 R15: ffffffff87ca9468 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055557ee264a8 CR3: 000000010bb5c000 CR4: 00000000003526b0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:112 [inline] default_idle+0x17/0x30 arch/x86/kernel/process.c:754 arch_cpu_idle+0xd/0x20 arch/x86/kernel/process.c:791 default_idle_call+0x3f/0x80 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x1a0/0x470 kernel/sched/idle.c:326 cpu_startup_entry+0x48/0x70 kernel/sched/idle.c:424 start_secondary+0x12e/0x140 arch/x86/kernel/smpboot.c:314 common_startup_64+0x13b/0x157