rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2646 jiffies s: 107289 root: 0x1/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 27099 Comm: syz.2.7586 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:native_apic_msr_write+0x1c/0x50 arch/x86/include/asm/apic.h:202 Code: 08 00 00 31 c0 31 d2 0f 30 c3 0f 1f 40 00 81 ff cf 00 00 00 7f 0c 83 ff 20 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b <81> ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 RSP: 0018:ffffc900036d6ae8 EFLAGS: 00000002 RAX: ffffffff81381160 RBX: ffffffff8c651b88 RCX: 0000000000080000 RDX: ffffc90014a80000 RSI: 00000000000000f6 RDI: 00000000000003f0 RBP: 0000000000000000 R08: ffffc900036d6a67 R09: 1ffff920006dad4c R10: dffffc0000000000 R11: fffff520006dad4d R12: 0000000000000000 R13: dffffc0000000001 R14: dffffc0000000000 R15: 0000000000000000 FS: 00007f4fa65ba6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555571aea4e8 CR3: 0000000024bb6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31 irq_work_queue_on+0x13c/0x260 kernel/irq_work.c:165 rcu_read_unlock_special+0x3c9/0x510 kernel/rcu/tree_plugin.h:678 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426 rcu_read_unlock include/linux/rcupdate.h:823 [inline] __perf_event_output kernel/events/core.c:7741 [inline] perf_event_output_forward+0x271/0x2f0 kernel/events/core.c:7750 __perf_event_overflow+0x448/0x610 kernel/events/core.c:9496 perf_swevent_overflow+0x19b/0x230 kernel/events/core.c:9579 perf_swevent_event+0x458/0x570 kernel/events/core.c:-1 perf_tp_event+0x3e7/0xc30 kernel/events/core.c:10064 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10032 perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14 trace_irq_enable_rcuidle+0xd3/0x140 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x24/0x40 kernel/trace/trace_preemptirq.c:44 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:728 RIP: 0010:rcu_read_unlock_special+0x7f/0x510 kernel/rcu/tree_plugin.h:685 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 d2 33 95 7e 41 f7 c6 00 00 f0 00 74 40 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 42 c7 44 2b 08 RSP: 0018:ffffc900036d7400 EFLAGS: 00000206 RAX: db2e512663374600 RBX: 1ffff920006dae88 RCX: db2e512663374600 RDX: dffffc0000000000 RSI: ffffffff8a8c10a0 RDI: ffffffff8adf0d20 RBP: ffffc900036d74f0 R08: ffffffff90af72df R09: 1ffffffff215ee5b R10: dffffc0000000000 R11: fffffbfff215ee5c R12: 0000000000000246 R13: dffffc0000000000 R14: ffff8880b8e3b900 R15: 0000000000000001 __rcu_read_unlock+0x78/0xd0 kernel/rcu/tree_plugin.h:426 rcu_read_unlock include/linux/rcupdate.h:823 [inline] page_ext_put+0x91/0xb0 mm/page_ext.c:182 page_table_check_pte_set include/linux/page_table_check.h:83 [inline] set_pte_at arch/x86/include/asm/pgtable.h:1009 [inline] copy_present_pte mm/memory.c:1000 [inline] copy_pte_range mm/memory.c:1091 [inline] copy_pmd_range mm/memory.c:1177 [inline] copy_pud_range mm/memory.c:1214 [inline] copy_p4d_range mm/memory.c:1238 [inline] copy_page_range+0x24ea/0x3900 mm/memory.c:1332 dup_mmap kernel/fork.c:702 [inline] dup_mm kernel/fork.c:1546 [inline] copy_mm+0xec3/0x1690 kernel/fork.c:1595 copy_process+0x1979/0x4030 kernel/fork.c:2356 kernel_clone+0x24b/0x900 kernel/fork.c:2762 __do_sys_clone kernel/fork.c:2903 [inline] __se_sys_clone kernel/fork.c:2887 [inline] __x64_sys_clone+0x1a7/0x220 kernel/fork.c:2887 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f4fa579c799 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:00007f4fa65b9fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007f4fa5a15fa0 RCX: 00007f4fa579c799 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000004eb82000 RBP: 00007f4fa5832c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f4fa5a16038 R14: 00007f4fa5a15fa0 R15: 00007fff88ed1728