INFO: task syz.6.8476:10262 blocked for more than 143 seconds. Tainted: G U 6.14.0-rc1-syzkaller-00187-g8f6629c004b1 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.8476 state:D stack:28336 pid:10262 tgid:10250 ppid:4381 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 expkey_flush+0x18/0x90 fs/nfsd/export.c:252 write_flush.constprop.0+0x2a1/0x3a0 net/sunrpc/cache.c:1549 pde_write fs/proc/inode.c:330 [inline] proc_reg_write+0x23d/0x330 fs/proc/inode.c:342 vfs_write+0x24c/0x1150 fs/read_write.c:677 ksys_write+0x12b/0x250 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb1bf38cde9 RSP: 002b:00007fb1c01e6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fb1bf5a6240 RCX: 00007fb1bf38cde9 RDX: 0000000000000001 RSI: 0000400000000100 RDI: 0000000000000008 RBP: 00007fb1bf40e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb1bf5a6240 R15: 00007ffc0068e658 INFO: lockdep is turned off. NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G U 6.14.0-rc1-syzkaller-00187-g8f6629c004b1 #0 Tainted: [U]=USER Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 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 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111