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BUG: KCSAN: data-race in fasync_remove_entry / kill_fasync

write to 0xffff88809a65c300 of 8 bytes by task 11912 on cpu 0:
 fasync_remove_entry+0xb7/0x120 fs/fcntl.c:884
 fasync_helper+0xc9/0xd6 fs/fcntl.c:983
 perf_fasync+0x64/0x90 kernel/events/core.c:6187
 __fput+0x455/0x500 fs/file_table.c:277
 ____fput+0x1b/0x30 fs/file_table.c:313
 task_work_run+0xba/0x120 kernel/task_work.c:123
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2ae/0x2c0 arch/x86/entry/common.c:165
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x38b/0x3b0 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88809a65c300 of 8 bytes by interrupt on cpu 1:
 kill_fasync+0x3c/0x170 fs/fcntl.c:1021
 perf_event_wakeup+0x115/0x160 kernel/events/core.c:6227
 perf_pending_event+0x129/0x170 kernel/events/core.c:6283
 irq_work_run_list+0x13e/0x190 kernel/irq_work.c:157
 irq_work_run+0x43/0x90 kernel/irq_work.c:174
 smp_irq_work_interrupt+0x3b/0xf0 arch/x86/kernel/irq_work.c:21
 irq_work_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:860
 __sanitizer_cov_trace_pc+0x27/0x50 kernel/kcov.c:187
 pmd_page_vaddr arch/x86/include/asm/pgtable.h:829 [inline]
 pte_offset_kernel arch/x86/include/asm/pgtable.h:874 [inline]
 map_pte mm/page_vma_mapped.c:18 [inline]
 page_vma_mapped_walk+0x6a1/0x13d0 mm/page_vma_mapped.c:216
 page_referenced_one+0x163/0x3f0 mm/rmap.c:778
 rmap_walk_anon+0x251/0x600 mm/rmap.c:1863
 rmap_walk+0x149/0x180 mm/rmap.c:1933
 page_referenced+0x19a/0x3c0 mm/rmap.c:888
 page_check_references mm/vmscan.c:987 [inline]
 shrink_page_list+0xd3e/0x2a40 mm/vmscan.c:1219
 reclaim_pages+0x5de/0x830 mm/vmscan.c:2138
 madvise_cold_or_pageout_pte_range+0xc31/0x1b20 mm/madvise.c:379
 walk_pmd_range mm/pagewalk.c:89 [inline]
 walk_pud_range mm/pagewalk.c:160 [inline]
 walk_p4d_range mm/pagewalk.c:193 [inline]
 walk_pgd_range mm/pagewalk.c:229 [inline]
 __walk_page_range+0xa6e/0x1550 mm/pagewalk.c:331
 walk_page_range+0x14c/0x280 mm/pagewalk.c:427
 madvise_pageout_page_range mm/madvise.c:520 [inline]
 madvise_pageout+0x15e/0x200 mm/madvise.c:556
 madvise_vma mm/madvise.c:945 [inline]
 do_madvise mm/madvise.c:1127 [inline]
 do_madvise+0x865/0x12c0 mm/madvise.c:1053
 __do_sys_madvise mm/madvise.c:1153 [inline]
 __se_sys_madvise mm/madvise.c:1151 [inline]
 __x64_sys_madvise+0x48/0x60 mm/madvise.c:1151
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 11919 Comm: syz-executor.0 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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