INFO: task syz.5.706:2661 blocked for more than 122 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.706 state:D stack:0 pid:2661 tgid:2660 ppid:2173 flags:0x00004004 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 super_lock+0x150/0x300 fs/super.c:115 super_lock_shared fs/super.c:140 [inline] iterate_supers+0x8a/0x560 fs/super.c:934 ksys_sync+0x95/0x160 fs/sync.c:103 __ia32_sys_sync+0x12/0x20 fs/sync.c:114 x64_sys_call+0x2a58/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:163 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: 0033:0x7f5e0f58ebe9 RSP: 002b:00007f5e1042e038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f5e0f7b5fa0 RCX: 00007f5e0f58ebe9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f5e0f7b5fa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5e0f7b6038 R14: 00007f5e0f7b5fa0 R15: 00007ffeaff1d848 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 9c3949e8c50b042e925ab8ad62694a1daa4311a1 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+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: 7654 Comm: syz.1.2237 Not tainted syzkaller #0 9c3949e8c50b042e925ab8ad62694a1daa4311a1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:__rdmsr arch/x86/include/asm/msr.h:86 [inline] RIP: 0010:native_read_msr arch/x86/include/asm/msr.h:120 [inline] RIP: 0010:get_debugctlmsr arch/x86/include/asm/debugreg.h:172 [inline] RIP: 0010:vcpu_enter_guest arch/x86/kvm/x86.c:10974 [inline] RIP: 0010:vcpu_run+0x40b4/0x7260 arch/x86/kvm/x86.c:11258 Code: 4c 89 f6 48 81 e6 aa 00 00 00 31 ff e8 95 c1 69 00 49 81 e6 aa 00 00 00 0f 85 ae 11 00 00 e8 a3 bc 69 00 b9 d9 01 00 00 0f 32 <49> 89 d6 49 c1 e6 20 49 09 c6 0f 1f 44 00 00 e8 88 bc 69 00 4c 89 RSP: 0018:ffffc9000e18f520 EFLAGS: 00000093 RAX: 0000000000000000 RBX: 1ffff11026461593 RCX: 00000000000001d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000e18f9b0 R08: ffff888139aa5f07 R09: 1ffff11027354be0 R10: dffffc0000000000 R11: ffffed1027354be1 R12: 1ffff11026461436 R13: ffff88813230a390 R14: 0000000000000000 R15: dffffc0000000000 FS: 00007f183ef876c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000145d44000 CR4: 00000000003526b0 Call Trace: kvm_arch_vcpu_ioctl_run+0x101a/0x1aa0 arch/x86/kvm/x86.c:11582 kvm_vcpu_ioctl+0x96f/0xee0 virt/kvm/kvm_main.c:4511 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0x132/0x1b0 fs/ioctl.c:893 __x64_sys_ioctl+0x7f/0xa0 fs/ioctl.c:893 x64_sys_call+0x1878/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:17 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: 0033:0x7f183e18ebe9 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:00007f183ef87038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f183e3b6090 RCX: 00007f183e18ebe9 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000013 RBP: 00007f183e211e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f183e3b6128 R14: 00007f183e3b6090 R15: 00007fff75d62b28