lkml.org 
[lkml]   [2019]   [Jan]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH] mm, compaction: Use free lists to quickly locate a migration target -fix
On Wed, 9 Jan 2019 11:13:44 +0000 Mel Gorman <mgorman@techsingularity.net> wrote:

> Full compaction of a node passes in negative orders which can lead to array
> boundary issues. While it could be addressed in the control flow of the
> primary loop, it would be fragile so explicitly check for the condition.
> This is a fix for the mmotm patch
> broken-out/mm-compaction-use-free-lists-to-quickly-locate-a-migration-target.patch
>
> ...
>
> --- a/mm/compaction.c
> +++ b/mm/compaction.c
> @@ -1206,6 +1206,10 @@ fast_isolate_freepages(struct compact_control *cc)
> bool scan_start = false;
> int order;
>
> + /* Full compaction passes in a negative order */
> + if (order <= 0)
> + return cc->free_pfn;
> +
> /*
> * If starting the scan, use a deeper search and use the highest
> * PFN found if a suitable one is not found.

`order' is uninitialized.

\
 
 \ /
  Last update: 2019-01-09 20:28    [W:0.514 / U:8.256 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site