rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=6713, q=187 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294953969-4294943467), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g6713 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:27976 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:
CPU: 1 PID: 5790 Comm: syz-executor330 Not tainted 6.6.102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:lock_acquire+0x1f2/0x410 kernel/locking/lockdep.c:5758
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00
RSP: 0018:ffffc90004457a80 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 50a67d818a7f5d00
RDX: 0000000000000000 RSI: ffffffff8aaacb40 RDI: ffffffff8afc66c0
RBP: ffffc90004457b88 R08: dffffc0000000000 R09: 1ffffffff21b46a6
R10: dffffc0000000000 R11: fffffbfff21b46a7 R12: 1ffff9200088af5c
R13: ffff88801d39a7a0 R14: 0000000000000246 R15: dffffc0000000000
FS:  00007fd9fa2e46c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd9fa2e3e40 CR3: 0000000072703000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 __might_fault+0xc6/0x120 mm/memory.c:5946
 _copy_from_user+0x2a/0xe0 lib/usercopy.c:14
 copy_from_user include/linux/uaccess.h:183 [inline]
 restore_altstack+0x9e/0x4a0 kernel/signal.c:4290
 __ia32_sys_rt_sigreturn+0x1f6/0x7b0 arch/x86/kernel/signal_64.c:263
 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: 0033:0x7fd9fa33aa19
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007fd9fa2e3c80 EFLAGS: 00000202 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007fd9fa3ad308 RCX: 00007fd9fa33aa19
RDX: 00007fd9fa2e3c80 RSI: 00007fd9fa2e3db0 RDI: 0000000000000021
RBP: 00007fd9fa3ad300 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000200000000140
R13: 000020000006b000 R14: 0000200000000100 R15: 0000200000000680
 </TASK>