syzbot

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BUG: KCSAN: data-race in find_get_context / find_get_context

write to 0xffff888237c2d4e0 of 4 bytes by task 4674 on cpu 1:
 find_get_context+0x310/0x5c0 kernel/events/core.c:4526
 __do_sys_perf_event_open kernel/events/core.c:11939 [inline]
 __se_sys_perf_event_open+0x852/0x25c0 kernel/events/core.c:11775
 __x64_sys_perf_event_open+0x63/0x70 kernel/events/core.c:11775
 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888237c2d4e0 of 4 bytes by task 4675 on cpu 0:
 find_get_context+0x300/0x5c0 kernel/events/core.c:4526
 __do_sys_perf_event_open kernel/events/core.c:11939 [inline]
 __se_sys_perf_event_open+0x852/0x25c0 kernel/events/core.c:11775
 __x64_sys_perf_event_open+0x63/0x70 kernel/events/core.c:11775
 do_syscall_64+0x34/0x50 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4675 Comm: syz-executor.2 Not tainted 5.12.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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