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BUG: KCSAN: data-race in __perf_event_overflow / __perf_event_set_bpf_prog

write to 0xffff8881215155d8 of 8 bytes by task 1604 on cpu 0:
 perf_event_set_bpf_handler kernel/events/core.c:10644 [inline]
 __perf_event_set_bpf_prog+0x419/0x470 kernel/events/core.c:11595
 _perf_ioctl kernel/events/core.c:6665 [inline]
 perf_ioctl+0x92e/0x15d0 kernel/events/core.c:6725
 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 0xffff8881215155d8 of 8 bytes by interrupt on cpu 1:
 __perf_event_overflow+0x252/0x920 kernel/events/core.c:10702
 perf_swevent_hrtimer+0x28d/0x310 kernel/events/core.c:12157
 __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
 kcsan_enable_current_nowarn+0x2c/0x80 kernel/kcsan/core.c:850
 page_slab mm/slab.h:139 [inline]
 virt_to_slab mm/slab.h:172 [inline]
 __memcg_slab_post_alloc_hook+0x2f4/0x540 mm/memcontrol.c:3231
 memcg_slab_post_alloc_hook mm/slub.c:2459 [inline]
 slab_post_alloc_hook mm/slub.c:4512 [inline]
 kmem_cache_alloc_bulk_noprof+0x46a/0x4c0 mm/slub.c:7247
 __io_alloc_req_refill+0x65/0x1e0 io_uring/io_uring.c:965
 io_alloc_req io_uring/io_uring.h:508 [inline]
 io_submit_sqes+0xa65/0x1270 io_uring/io_uring.c:2032
 __do_sys_io_uring_enter io_uring/io_uring.c:2603 [inline]
 __se_sys_io_uring_enter+0x1c9/0xf50 io_uring/io_uring.c:2538
 __x64_sys_io_uring_enter+0x78/0x90 io_uring/io_uring.c:2538
 x64_sys_call+0x1e16/0x3020 arch/x86/include/generated/asm/syscalls_64.h:427
 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 -> 0xffffc90001905000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 1593 Comm: syz.9.7982 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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