syzbot

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BUG: KCSAN: data-race in arch_perf_update_userpage / arch_perf_update_userpage

write to 0xffff888144ca8030 of 2 bytes by task 29605 on cpu 1:
 arch_perf_update_userpage+0xac/0x1f0
 perf_event_update_userpage+0x2d2/0x340 kernel/events/core.c:5886
 cpu_clock_event_add+0x11d/0x130 kernel/events/core.c:10698
 event_sched_in+0x7df/0xe90 kernel/events/core.c:2559
 group_sched_in kernel/events/core.c:2595 [inline]
 merge_sched_in kernel/events/core.c:3746 [inline]
 visit_groups_merge+0x943/0x1aa0 kernel/events/core.c:3696
 ctx_flexible_sched_in kernel/events/core.c:3788 [inline]
 ctx_sched_in+0x1e4/0x200 kernel/events/core.c:3833
 perf_event_sched_in kernel/events/core.c:2699 [inline]
 perf_event_context_sched_in kernel/events/core.c:3884 [inline]
 __perf_event_task_sched_in+0x37c/0x8d0 kernel/events/core.c:3927
 perf_event_task_sched_in include/linux/perf_event.h:1209 [inline]
 finish_task_switch+0x1ef/0x280 kernel/sched/core.c:4847
 context_switch kernel/sched/core.c:4975 [inline]
 __schedule+0x44a/0x6a0 kernel/sched/core.c:6253
 schedule+0x81/0xb0 kernel/sched/core.c:6326
 freezable_schedule include/linux/freezer.h:172 [inline]
 futex_wait_queue+0xd1/0x170 kernel/futex/waitwake.c:355
 futex_wait+0x126/0x350 kernel/futex/waitwake.c:656
 do_futex+0x28d/0x370 kernel/futex/syscalls.c:122
 __do_sys_futex kernel/futex/syscalls.c:199 [inline]
 __se_sys_futex+0xe8/0x370 kernel/futex/syscalls.c:180
 __x64_sys_futex+0x74/0x80 kernel/futex/syscalls.c:180
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

write to 0xffff888144ca8030 of 2 bytes by task 29610 on cpu 0:
 arch_perf_update_userpage+0xac/0x1f0
 perf_event_update_userpage+0x2d2/0x340 kernel/events/core.c:5886
 perf_mmap+0xd0d/0xe80 kernel/events/core.c:6354
 call_mmap include/linux/fs.h:2167 [inline]
 mmap_region+0xb00/0x10a0 mm/mmap.c:1786
 do_mmap+0x781/0xc20 mm/mmap.c:1575
 vm_mmap_pgoff+0x117/0x1f0 mm/util.c:519
 ksys_mmap_pgoff+0x265/0x320 mm/mmap.c:1623
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000 -> 0x0020

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 29610 Comm: syz-executor.4 Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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