lkml.org 
[lkml]   [2012]   [Nov]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[ 089/171] rbd: protect read of snapshot sequence number
Date
3.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Josh Durgin <josh.durgin@dreamhost.com>

(cherry picked from commit 403f24d3d51760a8b9368d595fa5f48c309f1a0f)

This is updated whenever a snapshot is added or deleted, and the
snapc pointer is changed with every refresh of the header.

Signed-off-by: Josh Durgin <josh.durgin@dreamhost.com>
Reviewed-by: Alex Elder <elder@dreamhost.com>
Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/block/rbd.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1683,7 +1683,9 @@ static int rbd_header_add_snap(struct rb
if (ret < 0)
return ret;

- dev->header.snapc->seq = new_snapid;
+ down_write(&dev->header_rwsem);
+ dev->header.snapc->seq = new_snapid;
+ up_write(&dev->header_rwsem);

return 0;
bad:



\
 
 \ /
  Last update: 2012-11-23 10:22    [W:0.659 / U:0.016 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site