rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=114493, q=171 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10500 (4295041443-4295030943), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10500 jiffies! g114493 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:27656 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0x1553/0x45a0 kernel/sched/core.c:6700
 schedule+0xbd/0x170 kernel/sched/core.c:6774
 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x313/0x1590 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x9d/0x3b0 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: 19211 Comm: syz.2.2822 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:__this_cpu_preempt_check+0x0/0x20 lib/smp_processor_id.c:65
Code: 48 89 da e8 c2 5b f4 ff 48 8b 74 24 30 48 c7 c7 20 90 1c 8b e8 b1 5b f4 ff e8 4c 80 ff ff eb a8 e8 e5 e8 ff ff 0f 1f 44 00 00 <f3> 0f 1e fa 48 89 fe 48 c7 c7 a0 8f 1c 8b e9 dd fe ff ff cc cc cc
RSP: 0018:ffffc900001f0bc8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: ffff888018f8da00 RCX: 0000000000000001
RDX: ffff888018f8da00 RSI: ffff8880579d5c98 RDI: ffffffff8acadb60
RBP: 0000000000000001 R08: ffff888018f8da00 R09: 0000000000000002
R10: 0000000000000001 R11: 0000000000010000 R12: 0000000000000002
R13: 0000000000000046 R14: ffff8880579d5c98 R15: ffff888018f8e530
FS:  00007f56ab8a16c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000058 CR3: 000000002f286000 CR4: 00000000003506e0
Call Trace:
 <IRQ>
 lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline]
 lock_is_held_type+0x104/0x190 kernel/locking/lockdep.c:5826
 lock_is_held include/linux/lockdep.h:288 [inline]
 signal_wake_up_state kernel/signal.c:772 [inline]
 signal_wake_up include/linux/sched/signal.h:457 [inline]
 complete_signal+0x7f7/0xca0 kernel/signal.c:1076
 send_sigqueue+0x48d/0x710 kernel/signal.c:2034
 posix_timer_event kernel/time/posix-timers.c:299 [inline]
 posix_timer_fn+0x16e/0x3d0 kernel/time/posix-timers.c:325
 __run_hrtimer kernel/time/hrtimer.c:1750 [inline]
 __hrtimer_run_queues+0x520/0xc40 kernel/time/hrtimer.c:1814
 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
 __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:lock_is_held_type+0x13e/0x190 kernel/locking/lockdep.c:5830
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 <48> 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0018:ffffc9001287fa38 EFLAGS: 00000206
RAX: ac826a8c08a8dc00 RBX: ffff888018f8da00 RCX: ac826a8c08a8dc00
RDX: 0000000000000000 RSI: ffffffff8acadb60 RDI: ffffffff8b1c8fa0
RBP: 0000000000000000 R08: ffffc9001287fe2f R09: 1ffff9200250ffc5
R10: dffffc0000000000 R11: fffff5200250ffc6 R12: dffffc0000000000
R13: 0000000000000246 R14: ffffffff8d132140 R15: 00000000ffffffff
 lock_is_held include/linux/lockdep.h:288 [inline]
 __might_resched+0x9f/0x630 kernel/sched/core.c:10173
 __might_fault+0x71/0x120 mm/memory.c:5966
 __clear_user arch/x86/include/asm/uaccess_64.h:167 [inline]
 clear_user arch/x86/include/asm/uaccess_64.h:191 [inline]
 copy_siginfo_to_user+0x5b/0xa0 kernel/signal.c:3374
 x64_setup_rt_frame+0x746/0xc40 arch/x86/kernel/signal_64.c:194
 setup_rt_frame arch/x86/kernel/signal.c:223 [inline]
 handle_signal arch/x86/kernel/signal.c:267 [inline]
 arch_do_signal_or_restart+0x42c/0x800 arch/x86/kernel/signal.c:312
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/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+0x61/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f56aa99cdd7
Code: 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89
RSP: 002b:00007f56ab8a10e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f56aac15fa8 RCX: 00007f56aa99cdd9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f56aac15fa8
RBP: 00007f56aac15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f56aac16038 R14: 00007ffc05fec6f0 R15: 00007ffc05fec7d8
 </TASK>