On 12/17/13, 4:30 PM, Dave Chinner wrote:

On Tue, Dec 17, 2013 at 02:18:25PM -0500, Matthew Wilcox wrote:

quoted

For v3, we've addressed the problem with unwritten extents that Dave
Chinner pointed out. 

No, you haven't addressed the problem. There is nothing in this
patch set that converts an unwritten extent after it is written to.
Hence on every subsequent read will return zeros because the block
is still marked as unwritten.

I'd really strongly encourage you guys to try running through xfstests.

IF you haven't seen this stuff fail yet, you're apparently not
testing these paths - I'm guessing xfstests may expose these holes
quite well.

I'd be happy to help you get up & running on xfstests if you need a
hand.

-Eric