syzbot

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BUG: KCSAN: data-race in __add_to_page_cache_locked / iomap_dio_complete

write to 0xffff888105de9480 of 8 bytes by task 6111 on cpu 1:
 __add_to_page_cache_locked+0x256/0x4e0 mm/filemap.c:914
 add_to_page_cache_lru+0xa0/0x1b0 mm/filemap.c:967
 page_cache_ra_unbounded+0x262/0x410 mm/readahead.c:221
 ondemand_readahead+0x579/0x7b0 mm/readahead.c:267
 page_cache_async_ra+0x165/0x190 mm/readahead.c:607
 page_cache_async_readahead include/linux/pagemap.h:902 [inline]
 filemap_readahead mm/filemap.c:2442 [inline]
 filemap_get_pages mm/filemap.c:2483 [inline]
 filemap_read+0x49d/0x1230 mm/filemap.c:2550
 generic_file_read_iter+0x75/0x2c0 mm/filemap.c:2701
 ext4_file_read_iter+0x1db/0x290 fs/ext4/file.c:73
 call_read_iter include/linux/fs.h:2108 [inline]
 new_sync_read fs/read_write.c:415 [inline]
 vfs_read+0x565/0x5d0 fs/read_write.c:496
 ksys_read+0xce/0x180 fs/read_write.c:634
 __do_sys_read fs/read_write.c:644 [inline]
 __se_sys_read fs/read_write.c:642 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:642
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888105de9480 of 8 bytes by task 6102 on cpu 0:
 iomap_dio_complete+0x31a/0x3c0 fs/iomap/direct-io.c:112
 iomap_dio_rw+0x4e/0x70 fs/iomap/direct-io.c:652
 ext4_dio_write_iter fs/ext4/file.c:568 [inline]
 ext4_file_write_iter+0xa4f/0x11d0 fs/ext4/file.c:678
 call_write_iter include/linux/fs.h:2114 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 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+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x773/0xda0 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 6102 Comm: syz-executor.2 Not tainted 5.13.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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Page cache invalidation failure on direct I/O.  Possible data corruption due to collision with buffered I/O!
File: /root/syzkaller-testdir801259789/syzkaller.iwxvrB/57/bus PID: 6102 Comm: syz-executor.2