rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10002 jiffies, g=23421, q=1065 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10003 (4294976711-4294966708), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10004 jiffies! g23421 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:0     pid:18    tgid:18    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 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_timeout+0x139/0x3a0 kernel/time/timer.c:2619
 rcu_gp_fqs_loop+0x2f2/0x12f0 kernel/rcu/tree.c:2053
 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:2255
 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
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 15572 Comm: syz.7.5126 Not tainted syzkaller #0 22de895e84cf4880b304a967638547f141894232
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:ffffc9000160fa80 EFLAGS: 00000283
RAX: 1ffff11024d4b6dc RBX: ffffffffffffff28 RCX: dffffc0000000000
RDX: ffffc90006234000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000160fad0 R08: ffff8881394199af R09: 0000000000000000
R10: ffff8881394199a0 R11: ffffed1027283336 R12: ffff888126a5b6c0
R13: ffff888110dadbb0 R14: ffff888126a5b6e0 R15: ffff888127f53500
FS:  00007f1b7aadf6c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3001b2 CR3: 000000012805e000 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: 0033:0x7f1b79b8efc9
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:00007f1b7aadf038 EFLAGS: 00000246 ORIG_RAX: 00000000000001ad
RAX: ffffffffffffffda RBX: 00007f1b79de5fa0 RCX: 00007f1b79b8efc9
RDX: ffffffffffffff9c RSI: 0000200000000140 RDI: 0000000000000005
RBP: 00007f1b79c11f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000180 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1b79de6038 R14: 00007f1b79de5fa0 R15: 00007ffdae6f4128
 </TASK>