rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=12241, q=555 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294958320-4294947818), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g12241 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
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:27400 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5380 [inline]
 __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
 schedule+0xbd/0x170 kernel/sched/core.c:6773
 schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6037 Comm: syz.2.27 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__lock_release kernel/locking/lockdep.c:5438 [inline]
RIP: 0010:lock_release+0x22d/0x8b0 kernel/locking/lockdep.c:5774
Code: 85 c0 0f 84 d7 01 00 00 4d 85 e4 0f 84 ff 02 00 00 4d 8d 74 24 24 4c 89 f0 48 c1 e8 03 42 0f b6 04 28 84 c0 0f 85 91 04 00 00 <41> 83 3e 00 0f 85 be 03 00 00 4d 8d 74 24 20 4c 89 f3 48 c1 eb 03
RSP: 0018:ffffc900038077c0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffff88807af473a0 RDI: ffff8880233ba8e0
RBP: ffffc900038078d0 R08: ffffffff8e4a8d6f R09: 1ffffffff1c951ad
R10: dffffc0000000000 R11: fffffbfff1c951ae R12: ffff8880233ba8e0
R13: dffffc0000000000 R14: ffff8880233ba904 R15: 0000000000000000
FS:  00007f47159ba6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffb981e7dac CR3: 000000005f78a000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 __clear_user arch/x86/include/asm/uaccess_64.h:167 [inline]
 copy_fpstate_to_sigframe+0x13c/0xbe0 arch/x86/kernel/fpu/signal.c:216
 get_sigframe+0x5ce/0x7c0 arch/x86/kernel/signal.c:142
 x64_setup_rt_frame+0x158/0xcd0 arch/x86/kernel/signal_64.c:175
 setup_rt_frame arch/x86/kernel/signal.c:223 [inline]
 handle_signal arch/x86/kernel/signal.c:267 [inline]
 arch_do_signal_or_restart+0x3fa/0x7b0 arch/x86/kernel/signal.c:312
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4714b8f6c9
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:00007f47159ba0e8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 00007f4714de5fa8 RCX: 00007f4714b8f6c9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f4714de5fac
RBP: 00007f4714de5fa0 R08: 0000000000745d1e R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4714de6038 R14: 00007ffe1f6c6aa0 R15: 00007ffe1f6c6b88
 </TASK>