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BUG: KCSAN: data-race in __filemap_add_folio / file_write_and_wait_range

read-write to 0xffff88810684b528 of 8 bytes by task 16795 on cpu 0:
 __filemap_add_folio+0x4c1/0x730 mm/filemap.c:903
 filemap_add_folio+0x70/0x160 mm/filemap.c:938
 __filemap_get_folio+0x2f1/0x5a0 mm/filemap.c:1927
 ext4_da_write_begin+0x2eb/0x550 fs/ext4/inode.c:2885
 generic_perform_write+0x1c9/0x410 mm/filemap.c:3930
 ext4_buffered_write_iter+0x1f6/0x370 fs/ext4/file.c:299
 ext4_file_write_iter+0x297/0xe10
 call_write_iter include/linux/fs.h:2087 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x760/0x8d0 fs/read_write.c:590
 ksys_write+0xeb/0x1a0 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:652
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff88810684b528 of 8 bytes by task 16808 on cpu 1:
 mapping_needs_writeback mm/filemap.c:626 [inline]
 file_write_and_wait_range+0x67/0x190 mm/filemap.c:778
 ext4_sync_file+0x133/0x6c0 fs/ext4/fsync.c:158
 vfs_fsync_range fs/sync.c:188 [inline]
 vfs_fsync fs/sync.c:202 [inline]
 do_fsync fs/sync.c:212 [inline]
 __do_sys_fdatasync fs/sync.c:225 [inline]
 __se_sys_fdatasync fs/sync.c:223 [inline]
 __x64_sys_fdatasync+0x84/0xd0 fs/sync.c:223
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x00000000000001f2 -> 0x00000000000001f4

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16808 Comm: syz-executor.0 Not tainted 6.8.0-rc7-syzkaller-00142-g3aaa8ce7a335 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
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