Re: [PATCH v6 0/2] huge_pmd_unshare migration and flushing

[Kirill A. Shutemov]

On Thu, Aug 23, 2018 at 08:59:15PM +0000, Mike Kravetz wrote:
> Correct a data corruption issue caused by improper handling of shared
> huge PMDs during page migration.  This issue was observed in a customer
> environment and can be recreated fairly easily with a test program.
> Patch 0001 addresses this issue only and is copied to stable with the
> intention that this will go to stable releases.  It has existed since
> the addition of shared huge PMD support.
> 
> While considering the issue above, Kirill Shutemov noticed that other
> callers of huge_pmd_unshare have potential issues with cache and TLB
> flushing.  A separate patch (0002) takes advantage of the new routine
> adjust_range_if_pmd_sharing_possible() to adjust flushing ranges in
> the cases where huge PMD sharing is possible.  There is no copy to
> stable for this patch as it has not been reported as an issue and
> discovered only via code inspection.

Looks good to me.

Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>

-- 
 Kirill A. Shutemov