rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (1 GPs behind) idle=fa64/1/0x4000000000000000 softirq=20292/20299 fqs=4608
	(t=10500 jiffies g=21841 q=16717 ncpus=2)
CPU: 1 PID: 6421 Comm: syz.2.480 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:should_fail_ex+0x4a/0x4d0 lib/fault-inject.c:119
Code: df 65 8b 05 60 ad d7 7b a9 00 01 ff 00 0f 84 ed 00 00 00 49 89 dd 49 c1 ed 03 43 80 7c 25 00 00 74 08 48 89 df e8 56 43 a6 fd <48> 83 3b 00 0f 84 16 01 00 00 4c 8d 7b 20 4c 89 f8 48 c1 e8 03 42
RSP: 0018:ffffc90004f9fb80 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff8d1c2740 RCX: 0000000000080000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff8d1c2740
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1c3ed56
R10: fffffbfff1c3ed56 R11: 1ffffffff1c3ed55 R12: dffffc0000000000
R13: 1ffffffff1a384e8 R14: 0000000000000001 R15: ffff8880562895c4
FS:  00007f75038506c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f61aff8 CR3: 0000000055391000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 _copy_from_user+0x2c/0x170 lib/usercopy.c:15
 copy_from_user include/linux/uaccess.h:161 [inline]
 restore_altstack+0x9a/0x4a0 kernel/signal.c:4257
 __ia32_sys_rt_sigreturn+0x660/0x790 arch/x86/kernel/signal.c:678
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f750298f749
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:00007f75038500e8 EFLAGS: 00000246
RAX: fffffffffffffffc RBX: 00007f7502be5fa8 RCX: 00007f750298f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f7502be5fa8
RBP: 00007f7502be5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7502be6038 R14: 00007ffd442bfc00 R15: 00007ffd442bfce8
 </TASK>