On Thu, Sep 24, 2020 at 01:56:08PM +0100, Matthew Wilcox (Oracle) wrote:
> For filesystems with block size < page size, we need to set all the
> per-block uptodate bits if the page was already uptodate at the time
> we create the per-block metadata. This can happen if the page is
> invalidated (eg by a write to drop_caches) but ultimately not removed
> from the page cache.
>
> This is a data corruption issue as page writeback skips blocks which
> are marked !uptodate.
>
> Fixes: 9dc55f1389f9 ("iomap: add support for sub-pagesize buffered I/O without buffer heads")
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
> Reported-by: Qian Cai <cai@xxxxxxxxxx>
> Cc: Brian Foster <bfoster@xxxxxxxxxx>
Looks good,
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
