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BUG: KCSAN: data-race in __perf_event_overflow / fasync_remove_entry

read to 0xffff888123df7af8 of 8 bytes by interrupt on cpu 1:
 __perf_event_overflow+0x11d/0x200 kernel/events/core.c:8192
 perf_swevent_hrtimer+0x261/0x280 kernel/events/core.c:9576
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x274/0x5f0 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1638
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 arch_local_irq_enable arch/x86/include/asm/paravirt.h:766 [inline]
 preempt_schedule_irq+0x4d/0x90 kernel/sched/core.c:4327
 restore_regs_and_return_to_kernel+0x0/0x25
 __write_once_size include/linux/compiler.h:247 [inline]
 write_comp_data+0x68/0x70 kernel/kcov.c:145
 radix_tree_load_root+0x6d/0x100 lib/radix-tree.c:404
 __radix_tree_lookup+0x5e/0x1b0 lib/radix-tree.c:767
 radix_tree_lookup+0x2b/0x40 lib/radix-tree.c:828
 wb_find_current include/linux/backing-dev.h:281 [inline]
 wb_get_create_current include/linux/backing-dev.h:307 [inline]
 balance_dirty_pages_ratelimited+0x4b9/0xb40 mm/page-writeback.c:1876
 generic_perform_write+0x22d/0x320 mm/filemap.c:3341
 __generic_file_write_iter+0x251/0x380 mm/filemap.c:3434
 ext4_file_write_iter+0x1bd/0xa00 fs/ext4/file.c:268
 call_write_iter include/linux/fs.h:1895 [inline]
 aio_write+0x1de/0x2d0 fs/aio.c:1583
 __io_submit_one fs/aio.c:1815 [inline]
 io_submit_one+0x639/0xe70 fs/aio.c:1862
 __do_sys_io_submit fs/aio.c:1921 [inline]
 __se_sys_io_submit fs/aio.c:1891 [inline]
 __x64_sys_io_submit+0x104/0x2d0 fs/aio.c:1891
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff888123df7af8 of 8 bytes by task 27164 on cpu 0:
 fasync_remove_entry+0xba/0x120 fs/fcntl.c:882
 fasync_helper+0xcf/0xdc fs/fcntl.c:981
 perf_fasync+0x6c/0xa0 kernel/events/core.c:5917
 __fput+0x46a/0x520 fs/file_table.c:277
 ____fput+0x1f/0x30 fs/file_table.c:313
 task_work_run+0xf6/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x353/0x370 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 27164 Comm: syz-executor.3 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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