From: Joe Thornber Date: Wed, 30 Oct 2013 17:11:58 +0000 (+0000) Subject: dm cache: fix a race condition between queuing new migrations and quiescing for a... X-Git-Tag: v3.13-rc1~97^2~25 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=66cb1910df17b38334153462ec8166e48058035f;p=pandora-kernel.git dm cache: fix a race condition between queuing new migrations and quiescing for a shutdown The code that was trying to do this was inadequate. The postsuspend method (in ioctl context), needs to wait for the worker thread to acknowledge the request to quiesce. Otherwise the migration count may drop to zero temporarily before the worker thread realises we're quiescing. In this case the target will be taken down, but the worker thread may have issued a new migration, which will cause an oops when it completes. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org # 3.9+ --- Reading git-diff-tree failed