rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=6737, q=27 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294954411-4294943909), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g6737 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:27752 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: 5814 Comm: syz-executor558 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__lock_acquire+0x12c5/0x7c80 kernel/locking/lockdep.c:5134
Code: b6 04 00 84 c0 0f 85 fc 5c 00 00 83 3d e3 cb 83 15 00 0f 84 e7 04 00 00 31 db 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 00 00 <74> 12 48 89 df e8 a1 c2 75 00 49 b8 00 00 00 00 00 fc ff df 48 83
RSP: 0018:ffffc90004a3f760 EFLAGS: 00000046
RAX: 1ffffffff20e49de RBX: ffffffff90724ef0 RCX: ffffffff81671850
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90da7530
RBP: ffffc90004a3f9a8 R08: dffffc0000000000 R09: 1ffffffff21b4ea6
R10: dffffc0000000000 R11: fffffbfff21b4ea7 R12: 00000000cccc4974
R13: ffff888029d98000 R14: 000000007dacc90d R15: ffff888029d98b00
FS:  0000555571e26480(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000006b000 CR3: 000000002e8bd000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
 __might_fault+0xc6/0x120 mm/memory.c:5946
 __copy_from_user include/linux/uaccess.h:97 [inline]
 check_xstate_in_sigframe arch/x86/kernel/fpu/signal.c:35 [inline]
 __fpu_restore_sig arch/x86/kernel/fpu/signal.c:348 [inline]
 fpu__restore_sig+0x19f/0x10e0 arch/x86/kernel/fpu/signal.c:493
 restore_sigcontext arch/x86/kernel/signal_64.c:95 [inline]
 __ia32_sys_rt_sigreturn+0x65d/0x7b0 arch/x86/kernel/signal_64.c:266
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9c5e25d119
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 19 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffd12bce18 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007f9c5e25d119
RDX: 000020000006b000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000000 R08: 00007f9c5e2ba33c R09: 00007f9c5e2ba33c
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9c5e2ba33c
R13: 00007f9c5e2b4106 R14: 00007fffd12bce60 R15: 0000000000000000
 </TASK>