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BUG: KCSAN: data-race in perf_event_update_userpage / perf_event_update_userpage

read-write to 0xffff88816241e008 of 4 bytes by task 1046 on cpu 0:
 perf_event_update_userpage+0x252/0x420 kernel/events/core.c:5886
 perf_mmap+0xa58/0xc10 kernel/events/core.c:6374
 call_mmap include/linux/fs.h:2196 [inline]
 mmap_region+0x9bb/0x13b0 mm/mmap.c:2625
 do_mmap+0x66d/0xa40 mm/mmap.c:1412
 vm_mmap_pgoff+0x117/0x1f0 mm/util.c:520
 ksys_mmap_pgoff+0x265/0x320 mm/mmap.c:1458
 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

read-write to 0xffff88816241e008 of 4 bytes by task 1047 on cpu 1:
 perf_event_update_userpage+0x252/0x420 kernel/events/core.c:5886
 cpu_clock_event_add+0x11d/0x130 kernel/events/core.c:10828
 event_sched_in+0x827/0xf50 kernel/events/core.c:2536
 group_sched_in kernel/events/core.c:2572 [inline]
 merge_sched_in kernel/events/core.c:3764 [inline]
 visit_groups_merge+0x91d/0x1d30 kernel/events/core.c:3708
 ctx_flexible_sched_in+0x4e/0x70 kernel/events/core.c:3806
 ctx_sched_in+0x1c2/0x1d0 kernel/events/core.c:3853
 perf_event_context_sched_in+0x27b/0x4e0 kernel/events/core.c:3903
 __perf_event_task_sched_in+0x6f/0x390 kernel/events/core.c:3936
 perf_event_task_sched_in include/linux/perf_event.h:1265 [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
 futex_wait_queue kernel/futex/waitwake.c:355 [inline]
 futex_wait+0x1a5/0x420 kernel/futex/waitwake.c:656
 do_futex+0x283/0x2b0 kernel/futex/syscalls.c:106
 __do_sys_futex kernel/futex/syscalls.c:183 [inline]
 __se_sys_futex+0xe8/0x350 kernel/futex/syscalls.c:164
 __x64_sys_futex+0x74/0x80 kernel/futex/syscalls.c:164
 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: 1047 Comm: syz-executor.3 Not tainted 6.1.0-rc4-syzkaller-00372-gaf7a05689189-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
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