watchdog: BUG: soft lockup - CPU#0 stuck for 152s! [syz.9.31086:15168]
CPU#0 Utilization every 22s during lockup:
	#1: 100% system,	  1% softirq,	  1% hardirq,	  0% idle
	#2: 100% system,	  1% softirq,	  1% hardirq,	  0% idle
	#3:  99% system,	  1% softirq,	  1% hardirq,	  0% idle
	#4:  99% system,	  1% softirq,	  1% hardirq,	  0% idle
	#5: 100% system,	  1% softirq,	  1% hardirq,	  0% idle
Modules linked in:
CPU: 0 UID: 0 PID: 15168 Comm: syz.9.31086 Not tainted syzkaller #0 815521559dbd70f1614977c300fd16d58acb59ef
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:next_peer fs/pnode.c:19 [inline]
RIP: 0010:do_make_slave fs/pnode.c:100 [inline]
RIP: 0010:change_mnt_propagation+0x112/0xb00 fs/pnode.c:128
Code: 24 20 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 f7 e8 47 51 e7 ff 4d 39 2e 0f 84 8f 00 00 00 <49> 81 c4 d8 00 00 00 4c 89 e0 48 c1 e8 03 48 b9 00 00 00 00 00 fc
RSP: 0018:ffffc90003b6fa80 EFLAGS: 00000283
RAX: 1ffff11026ddd5fc RBX: ffffffffffffff28 RCX: dffffc0000000000
RDX: ffffc9000800b000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90003b6fad0 R08: ffff888151d0746f R09: 0000000000000000
R10: ffff888151d07460 R11: ffffed102a3a0e8e R12: ffff888136eeafc0
R13: ffff8881111c2cc0 R14: ffff888136eeafe0 R15: ffff888115f24540
FS:  00007fd24c9c76c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff73fdd5f98 CR3: 0000000150890000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 umount_tree+0xdfd/0xf70 fs/namespace.c:1803
 attach_recursive_mnt+0x6df/0x21e0 fs/namespace.c:2549
 do_move_mount+0x608/0x810 fs/namespace.c:3374
 __do_sys_move_mount fs/namespace.c:4308 [inline]
 __se_sys_move_mount+0x28b/0xad0 fs/namespace.c:4260
 __x64_sys_move_mount+0xc3/0xf0 fs/namespace.c:4260
 x64_sys_call+0x2342/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:430
 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: 0033:0x7fd24bb8efc9
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:00007fd24c9c7038 EFLAGS: 00000246 ORIG_RAX: 00000000000001ad
RAX: ffffffffffffffda RBX: 00007fd24bde5fa0 RCX: 00007fd24bb8efc9
RDX: ffffffffffffff9c RSI: 0000200000000140 RDI: 0000000000000004
RBP: 00007fd24bc11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000180 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd24bde6038 R14: 00007fd24bde5fa0 R15: 00007ffde38484a8
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 15181 Comm: syz.0.31091 Not tainted syzkaller #0 815521559dbd70f1614977c300fd16d58acb59ef
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:pv_native_safe_halt+0x17/0x20 arch/x86/kernel/paravirt.c:106
Code: cc cc cc b8 d3 45 d2 72 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d c3 02 3a 00 f3 0f 1e fa 55 48 89 e5 fb f4 <5d> e9 d3 54 02 00 cc cc cc b8 00 00 00 00 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003af7930 EFLAGS: 000002d3
RAX: ffffffff81439535 RBX: 0000000000000003 RCX: ffff888142f7b900
RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000003
RBP: ffffc90003af7930 R08: ffffffff8720d604 R09: 1ffffffff0e41ac0
R10: dffffc0000000000 R11: fffffbfff0e41ac1 R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000003 R15: 1ffff9200075ef28
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000003d40 CR3: 00000001235dc000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:112 [inline]
 kvm_wait+0x1ba/0x220 arch/x86/kernel/kvm.c:1064
 pv_wait arch/x86/include/asm/paravirt.h:596 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:466 [inline]
 __pv_queued_spin_lock_slowpath+0x78d/0xcc0 kernel/locking/qspinlock.c:508
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline]
 _raw_spin_lock+0x109/0x120 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 write_seqlock include/linux/seqlock.h:876 [inline]
 lock_mount_hash fs/namespace.c:215 [inline]
 mntput_no_expire+0x147/0x6c0 fs/namespace.c:1411
 mntput+0x63/0xd0 fs/namespace.c:1466
 path_put+0x5b/0x70 fs/namei.c:569
 free_fs_struct fs/fs_struct.c:90 [inline]
 exit_fs+0xe8/0x160 fs/fs_struct.c:108
 do_exit+0x98d/0x2630 kernel/exit.c:949
 do_group_exit+0x22a/0x300 kernel/exit.c:1095
 __do_sys_exit_group kernel/exit.c:1106 [inline]
 __se_sys_exit_group kernel/exit.c:1104 [inline]
 __x64_sys_exit_group+0x43/0x50 kernel/exit.c:1104
 x64_sys_call+0x2ed2/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:232
 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: 0033:0x7f107b18efc9
Code: Unable to access opcode bytes at 0x7f107b18ef9f.
RSP: 002b:00007ffd73291eb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f107b18efc9
RDX: 00007f107a3e5000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffd73291f1c R08: 0000001e73291faf R09: 00000000000927c0
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000004f
R13: 00000000000927c0 R14: 000000000016c6d3 R15: 00007ffd73291f70
 </TASK>