rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=0f1/1/0x4000000000000000 softirq=396917/396917 fqs=0 
	(detected by 0, t=10506 jiffies, g=510841, q=201)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 25568 Comm: syz.2.67662 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:360 [inline]
RIP: 0010:unwind_next_frame+0x9c4/0x1d90 arch/x86/kernel/unwind_orc.c:539
Code: 74 05 e8 9f 0d 89 00 48 8b 73 28 48 8d 4b 20 4c 89 ff 48 89 da e8 ac 69 f5 ff 85 c0 0f 85 5d 0b 00 00 4c 89 ff e8 2c 1c 00 00 <49> 89 c7 49 bd 00 00 00 00 00 fc ff df 48 8b 44 24 20 42 80 3c 28
RSP: 0000:ffffc90002fdf420 EFLAGS: 00000002
RAX: ffffffff8154e3b8 RBX: ffffc90002fdf540 RCX: 1ffff920005fbe01
RDX: 1ffffffff1c0c533 RSI: ffffffff8e062994 RDI: ffffc90002fdfea8
RBP: ffffc90002fdf588 R08: 0000000000000001 R09: ffffc90002fdf590
R10: dffffc0000000000 R11: fffff520005fbeb4 R12: 1ffffffff1c0c533
R13: ffffc90002fe0000 R14: ffffc90002fd8000 R15: ffffc90002fdfea8
FS:  00007f28f6f086c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f28f8cfa400 CR3: 000000006383e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff1 DR7: 0000000000000600
Call Trace:
 <TASK>
 perf_callchain_kernel+0x449/0x720 arch/x86/events/core.c:2783
 get_perf_callchain+0x356/0x460 kernel/events/callchain.c:200
 perf_callchain kernel/events/core.c:7606 [inline]
 perf_prepare_sample+0x352/0x1cd0 kernel/events/core.c:7633
 __perf_event_output kernel/events/core.c:7802 [inline]
 perf_event_output_forward+0x185/0x2e0 kernel/events/core.c:7822
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_tp_event+0x383/0xbf0 kernel/events/core.c:10047
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021
 perf_trace_lock+0x301/0x390 include/trace/events/lock.h:39
 trace_lock_release include/trace/events/lock.h:58 [inline]
 lock_release+0x84a/0x8a0 kernel/locking/lockdep.c:5634
 do_write_seqcount_end include/linux/seqlock.h:565 [inline]
 vtime_user_exit+0x2c8/0x3e0 kernel/sched/cputime.c:732
 __context_tracking_exit+0x4c/0x80 kernel/context_tracking.c:160
 user_exit_irqoff include/linux/context_tracking.h:47 [inline]
 __enter_from_user_mode kernel/entry/common.c:22 [inline]
 irqentry_enter_from_user_mode+0x22/0x40 kernel/entry/common.c:314
 irqentry_enter+0xf/0x50 kernel/entry/common.c:332
 sysvec_irq_work+0xa/0xc0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0033:0x7f28f8caccb9
Code: 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 01 48
RSP: 002b:00007f28f6f08028 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f28f8f27fa0 RCX: 00007f28f8caccb9
RDX: 0000200000001ac0 RSI: 0000000000005452 RDI: 0000000000000003
RBP: 00007f28f8d1abf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f28f8f28038 R14: 00007f28f8f27fa0 R15: 00007ffc86db6678
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10505 jiffies! g510841 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=182252
rcu: rcu_preempt kthread starved for 10506 jiffies! g510841 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27152 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2be/0x11d0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x9b/0x370 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </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: 25568 Comm: syz.2.67662 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:unwind_next_frame+0xb9b/0x1d90 arch/x86/kernel/unwind_orc.c:-1
Code: e9 53 01 00 00 80 3d 1a 18 41 0c 00 0f 85 96 09 00 00 c6 05 0d 18 41 0c 01 48 c7 c7 60 8f 28 8a be 03 00 00 00 e9 31 07 00 00 <48> 89 54 24 50 48 8d 7b 08 48 89 f8 48 c1 e8 03 42 80 3c 28 00 74
RSP: 0000:ffffc90002fdf460 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffffc90002fdf580 RCX: ffffffff8dfc0188
RDX: 1ffffffff1d32e57 RSI: ffffffff8e997284 RDI: ffffc90002fdff58
RBP: ffffc90002fdf5c8 R08: 0000000000000028 R09: ffffc90002fdf5d0
R10: dffffc0000000000 R11: fffff520005fbebc R12: 1ffffffff1d32e57
R13: dffffc0000000000 R14: ffffffff8e9972b8 R15: ffffffff8e9972b9
FS:  00007f28f6f086c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f28f8cfa400 CR3: 000000006383e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff1 DR7: 0000000000000600
Call Trace:
 <TASK>
 perf_callchain_kernel+0x449/0x720 arch/x86/events/core.c:2783
 get_perf_callchain+0x356/0x460 kernel/events/callchain.c:200
 perf_callchain kernel/events/core.c:7606 [inline]
 perf_prepare_sample+0x352/0x1cd0 kernel/events/core.c:7633
 __perf_event_output kernel/events/core.c:7802 [inline]
 perf_event_output_forward+0x185/0x2e0 kernel/events/core.c:7822
 __perf_event_overflow+0x364/0x530 kernel/events/core.c:9515
 perf_tp_event+0x383/0xbf0 kernel/events/core.c:10047
 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10021
 perf_trace_lock+0x301/0x390 include/trace/events/lock.h:39
 trace_lock_release include/trace/events/lock.h:58 [inline]
 lock_release+0x84a/0x8a0 kernel/locking/lockdep.c:5634
 do_write_seqcount_end include/linux/seqlock.h:565 [inline]
 vtime_user_enter+0x1f0/0x2d0 kernel/sched/cputime.c:718
 __context_tracking_enter+0x60/0x90 kernel/context_tracking.c:82
 user_enter_irqoff include/linux/context_tracking.h:41 [inline]
 __exit_to_user_mode kernel/entry/common.c:136 [inline]
 irqentry_exit_to_user_mode+0x29/0x30 kernel/entry/common.c:322
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0033:0x7f28f8caccb9
Code: 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 01 48
RSP: 002b:00007f28f6f08028 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f28f8f27fa0 RCX: 00007f28f8caccb9
RDX: 0000200000001ac0 RSI: 0000000000005452 RDI: 0000000000000003
RBP: 00007f28f8d1abf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f28f8f28038 R14: 00007f28f8f27fa0 R15: 00007ffc86db6678
 </TASK>