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BUG: KCSAN: data-race in perf_event_update_userpage / perf_event_update_userpage

write to 0xffff88814033a018 of 8 bytes by task 7806 on cpu 0:
 perf_event_update_userpage+0x306/0x3b0 kernel/events/core.c:5954
 cpu_clock_event_add+0x11d/0x130 kernel/events/core.c:10794
 event_sched_in+0x781/0xe60 kernel/events/core.c:2601
 group_sched_in kernel/events/core.c:2637 [inline]
 merge_sched_in kernel/events/core.c:3818 [inline]
 visit_groups_merge+0x943/0x1a50 kernel/events/core.c:3762
 ctx_flexible_sched_in kernel/events/core.c:3860 [inline]
 ctx_sched_in+0x221/0x240 kernel/events/core.c:3908
 perf_event_sched_in kernel/events/core.c:2741 [inline]
 perf_event_context_sched_in kernel/events/core.c:3959 [inline]
 __perf_event_task_sched_in+0x37c/0x8d0 kernel/events/core.c:4002
 perf_event_task_sched_in include/linux/perf_event.h:1213 [inline]
 finish_task_switch+0x1ef/0x280 kernel/sched/core.c:4948
 context_switch kernel/sched/core.c:5076 [inline]
 __schedule+0x44b/0x6c0 kernel/sched/core.c:6382
 preempt_schedule_common kernel/sched/core.c:6547 [inline]
 __cond_resched+0x3f/0x90 kernel/sched/core.c:8154
 might_resched include/linux/kernel.h:110 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:49 [inline]
 __sb_start_write include/linux/fs.h:1729 [inline]
 sb_start_write include/linux/fs.h:1799 [inline]
 mnt_want_write+0x2c/0x1a0 fs/namespace.c:393
 open_last_lookups fs/namei.c:3389 [inline]
 path_openat+0x531/0x1f30 fs/namei.c:3606
 do_filp_open+0x105/0x220 fs/namei.c:3636
 do_sys_openat2+0xb5/0x2b0 fs/open.c:1214
 do_sys_open fs/open.c:1230 [inline]
 __do_sys_creat fs/open.c:1306 [inline]
 __se_sys_creat fs/open.c:1300 [inline]
 __x64_sys_creat+0x62/0x80 fs/open.c:1300
 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+0x44/0xae

write to 0xffff88814033a018 of 8 bytes by task 7805 on cpu 1:
 perf_event_update_userpage+0x306/0x3b0 kernel/events/core.c:5954
 perf_mmap+0xd34/0xeb0 kernel/events/core.c:6435
 call_mmap include/linux/fs.h:2086 [inline]
 mmap_region+0xb04/0x10b0 mm/mmap.c:1791
 do_mmap+0x781/0xc20 mm/mmap.c:1582
 vm_mmap_pgoff+0x117/0x1f0 mm/util.c:519
 ksys_mmap_pgoff+0x265/0x320 mm/mmap.c:1628
 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+0x44/0xae

value changed: 0x0000000000000000 -> 0x00000000008620bd

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7805 Comm: syz-executor.1 Not tainted 5.17.0-syzkaller-10753-gbddac7c1e02b-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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