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BUG: KCSAN: data-race in perf_event_update_userpage / perf_event_update_userpage

read-write to 0xffff8881377ed008 of 4 bytes by task 4290 on cpu 0:
 perf_event_update_userpage+0x233/0x450 kernel/events/core.c:6059
 cpu_clock_event_add+0x116/0x130 kernel/events/core.c:11094
 event_sched_in+0x451/0x670 kernel/events/core.c:2514
 group_sched_in kernel/events/core.c:2546 [inline]
 merge_sched_in kernel/events/core.c:3799 [inline]
 visit_groups_merge+0xbe0/0x1b90 kernel/events/core.c:3744
 ctx_flexible_sched_in+0xa0/0xf0 kernel/events/core.c:3852
 ctx_sched_in+0x1b0/0x1c0 kernel/events/core.c:3905
 perf_event_sched_in kernel/events/core.c:2642 [inline]
 perf_event_context_sched_in kernel/events/core.c:3951 [inline]
 __perf_event_task_sched_in+0x470/0x790 kernel/events/core.c:3980
 perf_event_task_sched_in include/linux/perf_event.h:1442 [inline]
 finish_task_switch+0x1ec/0x280 kernel/sched/core.c:5248
 context_switch kernel/sched/core.c:5384 [inline]
 __schedule+0x63b/0x8c0 kernel/sched/core.c:6710
 schedule+0x51/0x80 kernel/sched/core.c:6786
 schedule_hrtimeout_range_clock+0x15e/0x200 kernel/time/hrtimer.c:2301
 schedule_hrtimeout_range+0x29/0x30 kernel/time/hrtimer.c:2364
 poll_schedule_timeout fs/select.c:244 [inline]
 do_poll fs/select.c:965 [inline]
 do_sys_poll+0xa13/0xc00 fs/select.c:1015
 __do_sys_ppoll fs/select.c:1121 [inline]
 __se_sys_ppoll+0x1af/0x1f0 fs/select.c:1101
 __x64_sys_ppoll+0x67/0x80 fs/select.c:1101
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read-write to 0xffff8881377ed008 of 4 bytes by task 4300 on cpu 1:
 perf_event_update_userpage+0x233/0x450 kernel/events/core.c:6059
 perf_mmap+0xa46/0xcb0 kernel/events/core.c:6547
 call_mmap include/linux/fs.h:1876 [inline]
 mmap_region+0x901/0x14c0 mm/mmap.c:2745
 do_mmap+0x69c/0xaa0 mm/mmap.c:1362
 vm_mmap_pgoff+0x12f/0x240 mm/util.c:543
 ksys_mmap_pgoff+0x2b8/0x330 mm/mmap.c:1408
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 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: 4300 Comm: syz-executor.4 Not tainted 6.4.0-syzkaller-11311-g24be4d0b46bb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
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