rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=b57/1/0x4000000000000002 softirq=19927/19927 fqs=0 
	(detected by 1, t=10505 jiffies, g=24685, q=793)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9115 Comm: syz.1.1450 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:check_wait_context kernel/locking/lockdep.c:-1 [inline]
RIP: 0010:__lock_acquire+0x5a6/0x7d10 kernel/locking/lockdep.c:4962
Code: 93 d0 14 00 0f 84 fe 01 00 00 31 db 48 81 c3 b8 00 00 00 48 89 d8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 33 62 00 00 44 0f b6 33 <48> 8b 44 24 58 0f b6 04 10 84 c0 0f 85 42 62 00 00 41 8b 04 24 89
RSP: 0018:ffffc9000327ec40 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff8fb5bff8 RCX: ffffffff815d0b6a
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff901d30c0
RBP: ffffc9000327ee90 R08: ffffffff901d30c7 R09: 1ffffffff203a618
R10: dffffc0000000000 R11: fffffbfff203a619 R12: ffff88802243c708
R13: ffff88802243bb80 R14: 0000000000000002 R15: ffff88802243c6e8
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000fd000 CR3: 000000000c08e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:313
 rcu_read_lock include/linux/rcupdate.h:740 [inline]
 __perf_output_begin kernel/events/ring_buffer.c:163 [inline]
 perf_output_begin_forward+0xa5/0xa40 kernel/events/ring_buffer.c:271
 __perf_event_output kernel/events/core.c:7804 [inline]
 perf_event_output_forward+0x19b/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_preemptirq_template+0x2aa/0x360 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 e2 f0 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc9000327f760 EFLAGS: 00000206
RAX: 9dce112124480400 RBX: 1ffff9200064fef0 RCX: 9dce112124480400
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f800
RBP: ffffc9000327f830 R08: ffffffff901d30c7 R09: 1ffffffff203a618
R10: dffffc0000000000 R11: fffffbfff203a619 R12: ffffffff8c322f00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 __unlock_page_memcg+0xea/0x100 mm/memcontrol.c:2093
 zap_pte_range mm/memory.c:1384 [inline]
 zap_pmd_range mm/memory.c:1505 [inline]
 zap_pud_range mm/memory.c:1534 [inline]
 zap_p4d_range mm/memory.c:1555 [inline]
 unmap_page_range+0xf96/0x2500 mm/memory.c:1576
 unmap_vmas+0x131/0x250 mm/memory.c:1653
 exit_mmap+0x3b9/0x640 mm/mmap.c:3216
 __mmput+0x115/0x3b0 kernel/fork.c:1127
 exit_mm+0x588/0x6e0 kernel/exit.c:550
 do_exit+0x5a9/0x20c0 kernel/exit.c:870
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 __do_sys_exit_group kernel/exit.c:1008 [inline]
 __se_sys_exit_group kernel/exit.c:1006 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc4a0e29799
Code: Unable to access opcode bytes at RIP 0x7fc4a0e2976f.
RSP: 002b:00007ffd0a72ceb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc4a0e29799
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffd0a72cf1c R08: 0000000000000000 R09: 00000000000927c0
R10: 00007fc4a10a3218 R11: 0000000000000246 R12: 0000000000000113
R13: 00000000000927c0 R14: 0000000000030359 R15: 00007ffd0a72cf70
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g24685 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=13036
rcu: rcu_preempt kthread starved for 10505 jiffies! g24685 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
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:27536 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:2117
 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9115 Comm: syz.1.1450 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:29 [inline]
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline]
RIP: 0010:rcu_is_watching+0x5a/0xa0 kernel/rcu/tree.c:1123
Code: 03 42 80 3c 38 00 74 08 4c 89 f7 e8 70 5d 59 00 48 c7 c3 08 b3 03 00 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 84 c0 75 2b <8b> 03 65 ff 0d f5 9e 9d 7e 74 08 24 01 5b 41 5e 41 5f c3 e8 56 ac
RSP: 0018:ffffc9000327eec0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff8880b903b308 RCX: 9dce112124480400
RDX: 0000000000000000 RSI: ffffffff8a79f7e0 RDI: ffffffff8a79f7a0
RBP: ffffc9000327eff0 R08: ffffffff8d89dc2f R09: 1ffffffff1b13b85
R10: dffffc0000000000 R11: fffffbfff1b13b86 R12: 1ffff9200064fde8
R13: dffffc0000000000 R14: ffffffff8be30820 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000fd000 CR3: 000000000c08e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 trace_lock_release include/trace/events/lock.h:58 [inline]
 lock_release+0xb5/0x8a0 kernel/locking/lockdep.c:5634
 __perf_output_begin kernel/events/ring_buffer.c:262 [inline]
 perf_output_begin_forward+0x79b/0xa40 kernel/events/ring_buffer.c:271
 __perf_event_output kernel/events/core.c:7804 [inline]
 perf_event_output_forward+0x19b/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_preemptirq_template+0x2aa/0x360 include/trace/events/preemptirq.h:14
 trace_irq_enable_rcuidle+0x108/0x180 include/trace/events/preemptirq.h:40
 trace_hardirqs_on+0x57/0x80 kernel/trace/trace_preemptirq.c:44
 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713
RIP: 0010:rcu_read_unlock_special+0x7f/0x4a0 kernel/rcu/tree_plugin.h:674
Code: eb 03 48 b8 f1 f1 f1 f1 f8 f2 f2 f2 4a 89 04 2b 42 c7 44 2b 08 f8 f3 f3 f3 65 44 8b 35 e2 f0 9c 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 20 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08
RSP: 0018:ffffc9000327f760 EFLAGS: 00000206
RAX: 9dce112124480400 RBX: 1ffff9200064fef0 RCX: 9dce112124480400
RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f800
RBP: ffffc9000327f830 R08: ffffffff901d30c7 R09: 1ffffffff203a618
R10: dffffc0000000000 R11: fffffbfff203a619 R12: ffffffff8c322f00
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000001
 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:422
 rcu_read_unlock include/linux/rcupdate.h:772 [inline]
 __unlock_page_memcg+0xea/0x100 mm/memcontrol.c:2093
 zap_pte_range mm/memory.c:1384 [inline]
 zap_pmd_range mm/memory.c:1505 [inline]
 zap_pud_range mm/memory.c:1534 [inline]
 zap_p4d_range mm/memory.c:1555 [inline]
 unmap_page_range+0xf96/0x2500 mm/memory.c:1576
 unmap_vmas+0x131/0x250 mm/memory.c:1653
 exit_mmap+0x3b9/0x640 mm/mmap.c:3216
 __mmput+0x115/0x3b0 kernel/fork.c:1127
 exit_mm+0x588/0x6e0 kernel/exit.c:550
 do_exit+0x5a9/0x20c0 kernel/exit.c:870
 do_group_exit+0x12e/0x300 kernel/exit.c:997
 __do_sys_exit_group kernel/exit.c:1008 [inline]
 __se_sys_exit_group kernel/exit.c:1006 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1006
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc4a0e29799
Code: Unable to access opcode bytes at RIP 0x7fc4a0e2976f.
RSP: 002b:00007ffd0a72ceb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc4a0e29799
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffd0a72cf1c R08: 0000000000000000 R09: 00000000000927c0
R10: 00007fc4a10a3218 R11: 0000000000000246 R12: 0000000000000113
R13: 00000000000927c0 R14: 0000000000030359 R15: 00007ffd0a72cf70
 </TASK>