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BUG: KCSAN: data-race in __perf_event_overflow / __perf_event_set_bpf_prog

write to 0xffff88811c988418 of 8 bytes by task 20790 on cpu 0:
 perf_event_set_bpf_handler kernel/events/core.c:10642 [inline]
 __perf_event_set_bpf_prog+0x419/0x470 kernel/events/core.c:11628
 _perf_ioctl kernel/events/core.c:6663 [inline]
 perf_ioctl+0x92e/0x15d0 kernel/events/core.c:6723
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583
 x64_sys_call+0x1563/0x3020 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811c988418 of 8 bytes by interrupt on cpu 1:
 __perf_event_overflow+0x252/0x920 kernel/events/core.c:10700
 perf_event_overflow kernel/events/core.c:10784 [inline]
 perf_swevent_hrtimer+0x28d/0x310 kernel/events/core.c:12195
 __run_hrtimer kernel/time/hrtimer.c:1785 [inline]
 __hrtimer_run_queues+0x218/0x4f0 kernel/time/hrtimer.c:1849
 hrtimer_interrupt+0x269/0x810 kernel/time/hrtimer.c:1911
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1f0 arch/x86/kernel/apic/apic.c:1062
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 preempt_count arch/x86/include/asm/preempt.h:27 [inline]
 get_ctx kernel/kcsan/core.c:206 [inline]
 check_access kernel/kcsan/core.c:750 [inline]
 __tsan_memcpy+0x241/0x3c0 kernel/kcsan/core.c:1365
 __mark_reg_unknown_imprecise kernel/bpf/verifier.c:2865 [inline]
 __mark_reg_unknown kernel/bpf/verifier.c:2877 [inline]
 __mark_reg_not_init kernel/bpf/verifier.c:2916 [inline]
 clean_func_state kernel/bpf/verifier.c:19634 [inline]
 clean_verifier_state kernel/bpf/verifier.c:19655 [inline]
 clean_live_states kernel/bpf/verifier.c:19774 [inline]
 is_state_visited kernel/bpf/verifier.c:20475 [inline]
 do_check+0xa31/0x9840 kernel/bpf/verifier.c:21255
 do_check_common+0xd0b/0x1630 kernel/bpf/verifier.c:24667
 do_check_main kernel/bpf/verifier.c:24750 [inline]
 bpf_check+0x2f78/0xcc30 kernel/bpf/verifier.c:26073
 bpf_prog_load+0xf76/0x1140 kernel/bpf/syscall.c:3089
 __sys_bpf+0x505/0x7e0 kernel/bpf/syscall.c:6228
 __do_sys_bpf kernel/bpf/syscall.c:6341 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6339 [inline]
 __x64_sys_bpf+0x41/0x50 kernel/bpf/syscall.c:6339
 x64_sys_call+0x10cb/0x3020 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0xffffc900128dc000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 20783 Comm: syz.2.3870 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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ip6_tunnel: ip6gretap1 xmit: Local address not yet configured!