does cache manager flush cache before handling noncache io?

NTFSD
1

APIs like ZwCreateFile and FltWriteFile have flags to perform noncached IO, does system flush dirty data in cache before handling noncachedio to keep cache consistency? Or it is possbile that noncached read can get stale data?

2

To be accurate, the file system instructs the cache manager to flush (read path) or flush and purge (write path). Check out the FAT sources.

Absent misbehaving filters, the only way data- staleness can occur is via careful abuse of sections …

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3

good, thanks rod