[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <94724f27bf02e417629d93101a3fbb0dcfe86c28.1420799385.git.jslaby@suse.cz>
Date: Fri, 9 Jan 2015 11:31:25 +0100
From: Jiri Slaby <jslaby@...e.cz>
To: stable@...r.kernel.org
Cc: linux-kernel@...r.kernel.org,
Weijie Yang <weijie.yang@...sung.com>,
Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>,
Seth Jennings <sjennings@...iantweb.net>,
Dan Streetman <ddstreet@...e.org>,
Minchan Kim <minchan@...nel.org>, Bob Liu <bob.liu@...cle.com>,
Andrew Morton <akpm@...ux-foundation.org>,
Linus Torvalds <torvalds@...ux-foundation.org>,
Jiri Slaby <jslaby@...e.cz>
Subject: [PATCH 3.12 16/78] mm: frontswap: invalidate expired data on a dup-store failure
From: Weijie Yang <weijie.yang@...sung.com>
3.12-stable review patch. If anyone has any objections, please let me know.
===============
commit fb993fa1a2f669215fa03a09eed7848f2663e336 upstream.
If a frontswap dup-store failed, it should invalidate the expired page
in the backend, or it could trigger some data corruption issue.
Such as:
1. use zswap as the frontswap backend with writeback feature
2. store a swap page(version_1) to entry A, success
3. dup-store a newer page(version_2) to the same entry A, fail
4. use __swap_writepage() write version_2 page to swapfile, success
5. zswap do shrink, writeback version_1 page to swapfile
6. version_2 page is overwrited by version_1, data corrupt.
This patch fixes this issue by invalidating expired data immediately
when meet a dup-store failure.
Signed-off-by: Weijie Yang <weijie.yang@...sung.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
Cc: Seth Jennings <sjennings@...iantweb.net>
Cc: Dan Streetman <ddstreet@...e.org>
Cc: Minchan Kim <minchan@...nel.org>
Cc: Bob Liu <bob.liu@...cle.com>
Signed-off-by: Andrew Morton <akpm@...ux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@...ux-foundation.org>
Signed-off-by: Jiri Slaby <jslaby@...e.cz>
---
mm/frontswap.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/mm/frontswap.c b/mm/frontswap.c
index c30eec536f03..f2a3571c6e22 100644
--- a/mm/frontswap.c
+++ b/mm/frontswap.c
@@ -244,8 +244,10 @@ int __frontswap_store(struct page *page)
the (older) page from frontswap
*/
inc_frontswap_failed_stores();
- if (dup)
+ if (dup) {
__frontswap_clear(sis, offset);
+ frontswap_ops->invalidate_page(type, offset);
+ }
}
if (frontswap_writethrough_enabled)
/* report failure so swap also writes to swap device */
--
2.2.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists