rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 1-.... } 2690 jiffies s: 9073 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: 6596 Comm: syz.2.537 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 RIP: 0010:check_kcov_mode kernel/kcov.c:189 [inline] RIP: 0010:write_comp_data kernel/kcov.c:241 [inline] RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x32/0x80 kernel/kcov.c:316 Code: d4 24 80 7e 65 8b 15 d5 24 80 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 1c 16 00 00 00 74 4e 8b 91 f8 15 00 00 <83> fa 03 75 43 48 8b 91 00 16 00 00 44 8b 89 fc 15 00 00 49 c1 e1 RSP: 0018:ffffc9000d77ee78 EFLAGS: 00000046 RAX: ffffffff81a4fa8b RBX: 0000000000000000 RCX: ffff88802b168000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000d77ef70 R08: ffffc9000d77eff7 R09: ffffc9000d77efc0 R10: dffffc0000000000 R11: fffff52001aefdff R12: dffffc0000000000 R13: ffff888077a7d400 R14: 0000000000000000 R15: dffffc0000000000 FS: 00007f1f939e06c0(0000) GS:ffff8880b8d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000002fb000 CR3: 00000000737f6000 CR4: 00000000003506e0 DR0: 00002000000002c0 DR1: 0000000000000b6e DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: perf_prepare_sample+0x161b/0x2020 kernel/events/core.c:7694 __perf_event_output kernel/events/core.c:7740 [inline] perf_event_output_forward+0x197/0x2f0 kernel/events/core.c:7760 __perf_event_overflow+0x457/0x630 kernel/events/core.c:9506 perf_swevent_overflow+0x19b/0x230 kernel/events/core.c:9589 perf_swevent_event+0x458/0x570 kernel/events/core.c:-1 perf_tp_event+0x36b/0xc10 kernel/events/core.c:10074 perf_trace_run_bpf_submit+0xf3/0x1c0 kernel/events/core.c:10042 perf_trace_preemptirq_template+0x268/0x320 include/trace/events/preemptirq.h:14 trace_irq_disable include/trace/events/preemptirq.h:36 [inline] trace_hardirqs_off_finish+0x13f/0x180 kernel/trace/trace_preemptirq.c:67 irqentry_enter+0x33/0x50 kernel/entry/common.c:385 sysvec_apic_timer_interrupt+0xa/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 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 68 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:ffffc9000d77f700 EFLAGS: 00000206 RAX: d40a0989d304f800 RBX: 1ffff92001aefee8 RCX: d40a0989d304f800 RDX: dffffc0000000000 RSI: ffffffff8a8c19a0 RDI: ffffffff8adf7160 RBP: ffffc9000d77f7f0 R08: ffffffff91934247 R09: 1ffffffff2326848 R10: dffffc0000000000 R11: fffffbfff2326849 R12: 0000000000000246 R13: dffffc0000000000 R14: ffff8880b8d3bb00 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] do_anonymous_page mm/memory.c:4231 [inline] handle_pte_fault mm/memory.c:5027 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x3bc3/0x3d40 mm/memory.c:5292 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0010:copy_user_enhanced_fast_string+0xa/0x40 arch/x86/lib/copy_user_64.S:166 Code: ff c9 75 f2 89 d1 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 31 c0 0f 01 ca c3 8d 0c ca 89 ca eb 20 0f 01 cb 83 fa 40 72 38 89 d1 a4 31 c0 0f 01 ca c3 89 ca eb 0a 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc9000d77fbc8 EFLAGS: 00050202 RAX: ffffffff8416c501 RBX: 000000000014000e RCX: 00000000000c56ea RDX: 000000000014000e RSI: 00002000002fb000 RDI: ffff88804127a924 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000006 R10: dffffc0000000000 R11: ffffed1008268001 R12: 00007fffffebeff2 R13: 1ffff92001aeff90 R14: ffff888041200000 R15: 00002000002806dc copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline] _copy_from_user+0xf4/0x170 lib/usercopy.c:23 copy_from_user include/linux/uaccess.h:161 [inline] generic_map_update_batch+0x48d/0x7f0 kernel/bpf/syscall.c:1704 bpf_map_do_batch+0x475/0x5f0 kernel/bpf/syscall.c:-1 __sys_bpf+0x6f7/0x780 kernel/bpf/syscall.c:-1 __do_sys_bpf kernel/bpf/syscall.c:5139 [inline] __se_sys_bpf kernel/bpf/syscall.c:5137 [inline] __x64_sys_bpf+0x78/0x90 kernel/bpf/syscall.c:5137 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: 0033:0x7f1f92b9e559 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:00007f1f939e0028 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007f1f92e25fa0 RCX: 00007f1f92b9e559 RDX: 0000000000000038 RSI: 0000200000000140 RDI: 000000000000001a RBP: 00007f1f92c35ab8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1f92e26038 R14: 00007f1f92e25fa0 R15: 00007fffe1b12548