Re: [RFC] iomap: fix race between readahead and direct write

From: yukuai (C)
Date: Sat Jan 18 2020 - 20:25:29 EST




On 2020/1/18 0:24, Darrick J. Wong wrote:
Does the problem go away if you apply[1]? If I understand the race
correctly, marking the extents unwritten and leaving them that way until
after we've written the disk should eliminate the exposure vector...?:)

Thank you for your response.

The patch [1] fixed the stale data exposure problem which was tested by
generic/042. I'm afarid it's completely a diffrent case for generic/418.

In generic/418, direct write wrote some data to disk successfully, while
buffer read left the correspond page uptodate with 0 content in
pagecache.

Thanks!
Yu Kuai