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BUG: KCSAN: data-race in perf_event_update_userpage / perf_event_update_userpage

read-write to 0xffff88814bbc4008 of 4 bytes by task 30656 on cpu 0:
 perf_event_update_userpage+0x252/0x420 kernel/events/core.c:5850
 cpu_clock_event_add+0x11d/0x130 kernel/events/core.c:10707
 event_sched_in+0x812/0xf40 kernel/events/core.c:2513
 group_sched_in kernel/events/core.c:2549 [inline]
 merge_sched_in kernel/events/core.c:3728 [inline]
 visit_groups_merge+0xb30/0x2040 kernel/events/core.c:3672
 ctx_flexible_sched_in+0x4e/0x70 kernel/events/core.c:3770
 ctx_sched_in+0x1c2/0x1d0 kernel/events/core.c:3817
 perf_event_context_sched_in+0x27b/0x4e0 kernel/events/core.c:3867
 __perf_event_task_sched_in+0x6f/0x390 kernel/events/core.c:3900
 perf_event_task_sched_in include/linux/perf_event.h:1231 [inline]
 finish_task_switch+0x1e4/0x260 kernel/sched/core.c:5057
 context_switch kernel/sched/core.c:5185 [inline]
 __schedule+0x50d/0x6e0 kernel/sched/core.c:6494
 schedule+0x51/0x80 kernel/sched/core.c:6570
 exit_to_user_mode_loop+0xe5/0x130 kernel/entry/common.c:157
 exit_to_user_mode_prepare kernel/entry/common.c:201 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x6a/0x90 kernel/entry/common.c:294
 do_syscall_64+0x37/0x70 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read-write to 0xffff88814bbc4008 of 4 bytes by task 30666 on cpu 1:
 perf_event_update_userpage+0x252/0x420 kernel/events/core.c:5850
 perf_mmap+0xa5e/0xc20 kernel/events/core.c:6338
 call_mmap include/linux/fs.h:2192 [inline]
 mmap_region+0xa68/0xff0 mm/mmap.c:1752
 do_mmap+0x67a/0xb20 mm/mmap.c:1540
 vm_mmap_pgoff+0x117/0x1f0 mm/util.c:552
 ksys_mmap_pgoff+0x265/0x320 mm/mmap.c:1586
 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: 0x00000000 -> 0x00000002

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 30666 Comm: syz-executor.5 Tainted: G        W          6.0.0-rc6-syzkaller-00210-gbf682942cd26-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
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