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BUG: KCSAN: data-race in __filemap_add_folio / filemap_write_and_wait_range

write to 0xffff888104a33be0 of 8 bytes by task 8530 on cpu 1:
 __filemap_add_folio+0x256/0x4d0 mm/filemap.c:931
 filemap_add_folio+0x6b/0x150 mm/filemap.c:984
 add_to_page_cache_lru+0x4e/0x70 mm/folio-compat.c:115
 filemap_create_page mm/filemap.c:2490 [inline]
 filemap_get_pages mm/filemap.c:2548 [inline]
 filemap_read+0x80e/0x1720 mm/filemap.c:2624
 generic_file_read_iter+0x75/0x2c0 mm/filemap.c:2775
 ext4_file_read_iter+0x1db/0x290
 call_read_iter include/linux/fs.h:2155 [inline]
 generic_file_splice_read+0x24f/0x330 fs/splice.c:311
 do_splice_to fs/splice.c:796 [inline]
 splice_direct_to_actor+0x2aa/0x650 fs/splice.c:870
 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+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888104a33be0 of 8 bytes by task 8540 on cpu 0:
 mapping_needs_writeback mm/filemap.c:638 [inline]
 filemap_write_and_wait_range+0x36/0x340 mm/filemap.c:702
 __iomap_dio_rw+0x490/0xf20 fs/iomap/direct-io.c:543
 iomap_dio_rw+0x30/0x70 fs/iomap/direct-io.c:656
 ext4_dio_write_iter fs/ext4/file.c:568 [inline]
 ext4_file_write_iter+0xaa9/0x11f0 fs/ext4/file.c:678
 call_write_iter include/linux/fs.h:2161 [inline]
 do_iter_readv_writev+0x2de/0x380 fs/read_write.c:725
 do_iter_write+0x192/0x5c0 fs/read_write.c:851
 vfs_iter_write+0x4c/0x70 fs/read_write.c:892
 iter_file_splice_write+0x43a/0x790 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+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+0x44/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000000091 -> 0x0000000000000092

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8540 Comm: syz-executor.1 Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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