From: Joe Thornber Date: Tue, 1 Mar 2016 10:58:44 +0000 (+0000) Subject: dm thin metadata: don't issue prefetches if a transaction abort has failed X-Git-Tag: v4.1.22~64 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=78243d0a1221f06af96a8952cd5ac71cd1fe5376;p=thirdparty%2Fkernel%2Fstable.git dm thin metadata: don't issue prefetches if a transaction abort has failed [ Upstream commit 2eae9e4489b4cf83213fa3bd508b5afca3f01780 ] If a transaction abort has failed then we can no longer use the metadata device. Typically this happens if the superblock is unreadable. This fix addresses a crash seen during metadata device failure testing. Fixes: 8a01a6af75 ("dm thin: prefetch missing metadata pages") Cc: stable@vger.kernel.org # 3.19+ Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin --- diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c index cde1d6749017c..9b4f73e55d7c1 100644 --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -1803,5 +1803,8 @@ bool dm_pool_metadata_needs_check(struct dm_pool_metadata *pmd) void dm_pool_issue_prefetches(struct dm_pool_metadata *pmd) { - dm_tm_issue_prefetches(pmd->tm); + down_read(&pmd->root_lock); + if (!pmd->fail_io) + dm_tm_issue_prefetches(pmd->tm); + up_read(&pmd->root_lock); }