rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=8653, q=6 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10503 (4294966741-4294956238), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10504 jiffies! g8653 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:28352 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5400 [inline]
 __schedule+0xf15/0x5c80 kernel/sched/core.c:6727
 __schedule_loop kernel/sched/core.c:6802 [inline]
 schedule+0xe7/0x270 kernel/sched/core.c:6817
 schedule_timeout+0x136/0x290 kernel/time/timer.c:2183
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:1631
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:1830
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
 </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: 5105 Comm: syz-executor447 Not tainted 6.7.0-rc6-next-20231222-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
RIP: 0010:__might_fault+0xa7/0x190 mm/memory.c:6050
Code: ee e8 bd b4 91 ff 48 b8 00 00 00 00 00 fc ff df 65 48 8b 1d 9b e8 3a 7e 48 8d bb 28 05 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 be 00 00 00 48 83 bb 28 05 00 00 00 74 b0 e8 74 39 bf ff 48
RSP: 0018:ffffc90003b47af0 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffff888067c28000 RCX: ffffffff81c8d9f2
RDX: 1ffff1100cf850a5 RSI: 0000000000000061 RDI: ffff888067c28528
RBP: 0000000000000061 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888067c28000 R14: 0000000000000000 R15: ffffc90003b47b78
FS:  00005555561f33c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002006b000 CR3: 0000000022a70000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 __copy_from_user include/linux/uaccess.h:97 [inline]
 check_xstate_in_sigframe arch/x86/kernel/fpu/signal.c:35 [inline]
 __fpu_restore_sig+0xe0/0x13a0 arch/x86/kernel/fpu/signal.c:348
 fpu__restore_sig+0x102/0x170 arch/x86/kernel/fpu/signal.c:496
 restore_sigcontext+0x4c4/0x690 arch/x86/kernel/signal_64.c:95
 __do_sys_rt_sigreturn+0x138/0x230 arch/x86/kernel/signal_64.c:263
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x62/0x6a
RIP: 0033:0x7fa177e2dfea
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 c3 64 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 23 65 02 00 8b 44 24
RSP: 002b:00007ffe88183300 EFLAGS: 00000293
RAX: fffffffffffffff7 RBX: 0000000000000006 RCX: 00007fa177e2dfea
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00000000000f4240 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00005555561f3370
R13: 0000000000000001 R14: 00007ffe88183390 R15: 00007ffe88183380
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.566 msecs