2017-05-05 07:24:56

by Jan Kara

Subject: [PATCH 0/4 v2] mm,dax: Fix data corruption due to mmap inconsistency

Hello,

this series fixes data corruption that can happen for DAX mounts when
page faults race with write(2) and as a result page tables get out of sync
with block mappings in the filesystem and thus data seen through mmap is
different from data seen through read(2).

The series passes testing with t_mmap_stale test program from Ross and also
other mmap related tests on DAX filesystem. Ross, what you think?

Honza

2017-05-08 17:27:07

by Ross Zwisler

Subject: Re: [PATCH 0/4 v2] mm,dax: Fix data corruption due to mmap inconsistency

On Fri, May 05, 2017 at 09:24:56AM +0200, Jan Kara wrote:
> Hello,
>
> this series fixes data corruption that can happen for DAX mounts when
> page faults race with write(2) and as a result page tables get out of sync
> with block mappings in the filesystem and thus data seen through mmap is
> different from data seen through read(2).
>
> The series passes testing with t_mmap_stale test program from Ross and also
> other mmap related tests on DAX filesystem. Ross, what you think?

I don't know if I have enough ext4-fu to properly review patch 3, but the rest
looks great (and that patch looks good to me as well, FWIW). Thanks for
fixing this!