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BUG: KCSAN: data-race in __delayacct_blkio_end / __delayacct_blkio_start

write to 0xffff88810101ecd8 of 8 bytes by task 8445 on cpu 1:
 __delayacct_blkio_start+0x35/0x40 kernel/delayacct.c:61
 delayacct_blkio_start include/linux/delayacct.h:119 [inline]
 __schedule+0x18c/0x550 kernel/sched/core.c:4485
 schedule+0x7f/0xb0 kernel/sched/core.c:4601
 io_schedule+0x3b/0x50 kernel/sched/core.c:6295
 wait_on_page_bit_common+0x633/0x910 mm/filemap.c:1273
 __lock_page_killable mm/filemap.c:1540 [inline]
 lock_page_maybe_drop_mmap mm/filemap.c:2570 [inline]
 filemap_fault+0x87a/0x12e0 mm/filemap.c:2735
 ext4_filemap_fault+0x4b/0x60 fs/ext4/inode.c:6192
 __do_fault mm/memory.c:3612 [inline]
 do_read_fault+0x403/0x760 mm/memory.c:4006
 do_fault mm/memory.c:4134 [inline]
 handle_pte_fault mm/memory.c:4374 [inline]
 __handle_mm_fault mm/memory.c:4509 [inline]
 handle_mm_fault+0xfeb/0x1770 mm/memory.c:4607
 do_user_addr_fault+0x33e/0x730 arch/x86/mm/fault.c:1372
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x91/0x290 arch/x86/mm/fault.c:1485
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:583

read to 0xffff88810101ecd8 of 8 bytes by task 8454 on cpu 0:
 delayacct_end kernel/delayacct.c:48 [inline]
 __delayacct_blkio_end+0x70/0xf0 kernel/delayacct.c:82
 delayacct_blkio_end include/linux/delayacct.h:125 [inline]
 try_to_wake_up+0x107/0x470 kernel/sched/core.c:2892
 wake_page_function+0xd9/0x200 mm/filemap.c:1080
 __wake_up_common+0xbc/0x130 kernel/sched/wait.c:93
 wake_up_page_bit+0xa4/0x190 mm/filemap.c:1113
 unlock_page mm/filemap.c:1465 [inline]
 filemap_map_pages+0x81b/0x9a0 mm/filemap.c:2871
 do_fault_around mm/memory.c:3967 [inline]
 do_read_fault+0x233/0x760 mm/memory.c:4001
 do_fault mm/memory.c:4134 [inline]
 handle_pte_fault mm/memory.c:4374 [inline]
 __handle_mm_fault mm/memory.c:4509 [inline]
 handle_mm_fault+0xfeb/0x1770 mm/memory.c:4607
 do_user_addr_fault+0x33e/0x730 arch/x86/mm/fault.c:1372
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x91/0x290 arch/x86/mm/fault.c:1485
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:583

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8454 Comm: syz-fuzzer Not tainted 5.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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