From: mel@skynet.ie (Mel Gorman)
To: akpm@linux-foundation.org
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, clameter@engr.sgi.com
Subject: [PATCH] 2.6.21-rc2-mm2 Fix boot problem on IA64 with CONFIG_HOLE_IN_ZONES and CONFIG_PAGE_GROUP_BY_MOBILITY
Date: Wed, 7 Mar 2007 21:13:59 +0000 [thread overview]
Message-ID: <20070307211359.GA6736@skynet.ie> (raw)
Usually, a mem_map is aligned on MAX_ORDER_NR_PAGES boundaries and the
struct pages are always valid. However, this is not always the case when
CONFIG_HOLES_IN_ZONE is set.
move_freepages_block() checks that pages within a MAX_ORDER_NR_PAGES block
are in the same zone using page_zone(). However, if an invalid page is
passed to page_zone(), it can result in breakage on machines requiring
CONFIG_HOLES_IN_ZONE. This patch avoids the use of page_zone() and instead
checks the PFNs against the PFN ranges of the zone. This fixes a boot
problem on IA64 using the config arch/ia64/configs/sn2_defconfig .
Credit to Christoph Lameter for testing, reporting the bug and verifying
this fixes the problem. Credit to Andy Whitcroft for giving the patch a
quick review to ensure no functionality was changed.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
diff -rup -X /usr/src/patchset-0.6/bin//dontdiff linux-2.6.21-rc2-mm2-clean/mm/page_alloc.c linux-2.6.21-rc2-mm2-ia64_movefreepages_fix/mm/page_alloc.c
--- linux-2.6.21-rc2-mm2-clean/mm/page_alloc.c 2007-03-07 09:36:31.000000000 +0000
+++ linux-2.6.21-rc2-mm2-ia64_movefreepages_fix/mm/page_alloc.c 2007-03-07 14:17:43.000000000 +0000
@@ -734,18 +734,19 @@ int move_freepages(struct zone *zone,
int move_freepages_block(struct zone *zone, struct page *page, int migratetype)
{
- unsigned long start_pfn;
+ unsigned long start_pfn, end_pfn;
struct page *start_page, *end_page;
start_pfn = page_to_pfn(page);
start_pfn = start_pfn & ~(MAX_ORDER_NR_PAGES-1);
start_page = pfn_to_page(start_pfn);
end_page = start_page + MAX_ORDER_NR_PAGES;
+ end_pfn = start_pfn + MAX_ORDER_NR_PAGES;
/* Do not cross zone boundaries */
- if (page_zone(page) != page_zone(start_page))
+ if (start_pfn < zone->zone_start_pfn)
start_page = page;
- if (page_zone(page) != page_zone(end_page))
+ if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages)
return 0;
return move_freepages(zone, start_page, end_page, migratetype);
--
Mel Gorman
Part-time Phd Student Linux Technology Center
University of Limerick IBM Dublin Software Lab
reply other threads:[~2007-03-07 21:14 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20070307211359.GA6736@skynet.ie \
--to=mel@skynet.ie \
--cc=akpm@linux-foundation.org \
--cc=clameter@engr.sgi.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®