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BUG: KCSAN: data-race in perf_event_update_userpage / perf_event_update_userpage

read-write to 0xffff88813d976008 of 4 bytes by task 20933 on cpu 1:
 perf_event_update_userpage+0x252/0x420 kernel/events/core.c:5858
 cpu_clock_event_add+0x11d/0x130 kernel/events/core.c:10749
 event_sched_in+0x827/0xf50 kernel/events/core.c:2521
 group_sched_in kernel/events/core.c:2557 [inline]
 merge_sched_in kernel/events/core.c:3736 [inline]
 visit_groups_merge+0x91d/0x1d30 kernel/events/core.c:3680
 ctx_flexible_sched_in+0x4e/0x70 kernel/events/core.c:3778
 ctx_sched_in+0x1c2/0x1d0 kernel/events/core.c:3825
 perf_event_context_sched_in+0x27b/0x4e0 kernel/events/core.c:3875
 __perf_event_task_sched_in+0x6f/0x390 kernel/events/core.c:3908
 perf_event_task_sched_in include/linux/perf_event.h:1254 [inline]
 finish_task_switch+0x1e4/0x260 kernel/sched/core.c:5065
 context_switch kernel/sched/core.c:5194 [inline]
 __schedule+0x511/0x6e0 kernel/sched/core.c:6503
 schedule+0x51/0x80 kernel/sched/core.c:6579
 exit_to_user_mode_loop+0xe5/0x130 kernel/entry/common.c:159
 exit_to_user_mode_prepare kernel/entry/common.c:203 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x6a/0x90 kernel/entry/common.c:296
 do_syscall_64+0x37/0x70 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read-write to 0xffff88813d976008 of 4 bytes by task 20932 on cpu 0:
 perf_event_update_userpage+0x3c1/0x420 kernel/events/core.c:5874
 perf_mmap+0xa58/0xc10 kernel/events/core.c:6346
 call_mmap include/linux/fs.h:2196 [inline]
 mmap_region+0x99a/0x12c0 mm/mmap.c:2624
 do_mmap+0x66d/0xa40 mm/mmap.c:1411
 vm_mmap_pgoff+0x117/0x1f0 mm/util.c:520
 ksys_mmap_pgoff+0x265/0x320 mm/mmap.c:1457
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000001 -> 0x00000003

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 20932 Comm: syz-executor.1 Not tainted 6.1.0-rc1-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
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