rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2630 jiffies s: 160097 root: 0x2/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3838 Comm: syz.3.8083 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__sanitizer_cov_trace_cmp8+0x7a/0x80 kernel/kcov.c:294 Code: c1 e1 05 4c 8d 51 28 4d 39 ca 77 1e 49 ff c0 4c 89 02 48 c7 44 0a 08 06 00 00 00 48 89 7c 0a 10 48 89 74 0a 18 48 89 44 0a 20 0f 1f 44 00 00 48 8b 04 24 65 48 8b 15 24 fa 7f 7e 65 8b 0d 25 RSP: 0018:ffffc900001e0618 EFLAGS: 00000006 RAX: ffffffff81a58517 RBX: ffff8880671eb600 RCX: ffff88807aad3b80 RDX: 0000000000010100 RSI: 00000000000003e8 RDI: 0000000000000020 RBP: 0000000000000000 R08: ffff8880671eba7b R09: 1ffff1100ce3d74f R10: dffffc0000000000 R11: ffffed100ce3d750 R12: 00000000000003e8 R13: 1ffff1100ce3d701 R14: ffff8880671eb808 R15: 0000000000000020 FS: 00007effc94fe6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fea97a4eaeb CR3: 0000000032ba4000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000008d24 DR2: 0000200000000300 DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __perf_event_account_interrupt+0x127/0x280 kernel/events/core.c:9388 __perf_event_overflow+0x9d/0x610 kernel/events/core.c:9445 perf_swevent_hrtimer+0x3ef/0x590 kernel/events/core.c:10927 __run_hrtimer kernel/time/hrtimer.c:1747 [inline] __hrtimer_run_queues+0x50b/0xd50 kernel/time/hrtimer.c:1811 hrtimer_interrupt+0x3c5/0x9c0 kernel/time/hrtimer.c:1873 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline] __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:list_empty include/linux/list.h:292 [inline] RIP: 0010:net_rx_action+0x78a/0xb20 net/core/dev.c:6791 Code: 44 24 18 48 8d 58 78 48 89 d8 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 83 20 9f f9 48 83 3b 00 74 07 e8 78 35 4e f9 eb 1e <48> 8b 84 24 00 01 00 00 48 8d 8c 24 00 01 00 00 48 39 c8 0f 84 14 RSP: 0018:ffffc900001e0c80 EFLAGS: 00000246 RAX: 1ffff110171e779f RBX: ffff8880b8f3bcf8 RCX: ffff88807aad3b80 RDX: 0000000000000100 RSI: 0000000000000126 RDI: 0000000000000001 RBP: ffffc900001e0df0 R08: ffffffff8e1fd76f R09: 1ffffffff1c3faed R10: dffffc0000000000 R11: fffffbfff1c3faee R12: ffffc900001e0d60 R13: dffffc0000000000 R14: 1ffff110171e77cb R15: 0000000000000006 handle_softirqs+0x2a1/0x930 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x9d/0xc0 arch/x86/kernel/irq_work.c:17 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 e2 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:ffffc9000473f400 EFLAGS: 00000206 RAX: 93560a3734e0e200 RBX: 1ffff920008e7e88 RCX: 93560a3734e0e200 RDX: dffffc0000000000 RSI: ffffffff8a8c1220 RDI: ffffffff8adf0f60 RBP: ffffc9000473f4f0 R08: ffffffff90af62df R09: 1ffffffff215ec5b R10: dffffc0000000000 R11: fffffbfff215ec5c R12: 0000000000000246 R13: dffffc0000000000 R14: ffff8880b8f3b900 R15: 0000000000000002 __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: 0033:0x7effc859c799 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:00007effc94fdfd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007effc8815fa0 RCX: 00007effc859c799 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006988b400 RBP: 00007effc8632bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007effc8816038 R14: 00007effc8815fa0 R15: 00007fffbb8c3758