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BUG: KCSAN: data-race in event_sched_out / perf_event_update_userpage

write to 0xffff888136aca0d0 of 8 bytes by task 8122 on cpu 0:
 perf_event_update_time kernel/events/core.c:649 [inline]
 perf_event_set_state kernel/events/core.c:666 [inline]
 event_sched_out+0x354/0x830 kernel/events/core.c:2293
 group_sched_out+0xf0/0x1f0 kernel/events/core.c:2319
 ctx_sched_out+0x391/0x450 kernel/events/core.c:3289
 task_ctx_sched_out kernel/events/core.c:2687 [inline]
 perf_event_context_sched_out kernel/events/core.c:3494 [inline]
 __perf_event_task_sched_out+0x679/0xf00 kernel/events/core.c:3597
 perf_event_task_sched_out include/linux/perf_event.h:1232 [inline]
 prepare_task_switch+0x13b/0x140 kernel/sched/core.c:4782
 context_switch kernel/sched/core.c:4924 [inline]
 __schedule+0x397/0x6a0 kernel/sched/core.c:6253
 preempt_schedule_common kernel/sched/core.c:6419 [inline]
 __cond_resched+0x3f/0x90 kernel/sched/core.c:8132
 might_resched include/linux/kernel.h:101 [inline]
 might_alloc include/linux/sched/mm.h:230 [inline]
 slab_pre_alloc_hook mm/slab.h:492 [inline]
 slab_alloc mm/slab.c:3306 [inline]
 __do_kmalloc mm/slab.c:3700 [inline]
 __kmalloc+0x65/0x370 mm/slab.c:3711
 kmalloc_array+0x2d/0x40 include/linux/slab.h:631
 kcalloc include/linux/slab.h:661 [inline]
 iter_file_splice_write+0xd5/0x790 fs/splice.c:628
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0x106/0x190 fs/splice.c:979
 do_sendfile+0x675/0xc40 fs/read_write.c:1245
 __do_sys_sendfile64 fs/read_write.c:1310 [inline]
 __se_sys_sendfile64 fs/read_write.c:1296 [inline]
 __x64_sys_sendfile64+0x102/0x140 fs/read_write.c:1296
 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

read to 0xffff888136aca0d0 of 8 bytes by task 8133 on cpu 1:
 __perf_update_times kernel/events/core.c:632 [inline]
 calc_timer_values kernel/events/core.c:5810 [inline]
 perf_event_update_userpage+0xcd/0x340 kernel/events/core.c:5865
 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: 0x0000000001ecbe72 -> 0x0000000001ed6103

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8133 Comm: syz-executor.4 Not tainted 5.16.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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