From: Jeff Moyer Date: Mon, 17 Oct 2011 10:57:23 +0000 (+0200) Subject: blk-flush: move the queue kick into X-Git-Tag: v3.2-rc1~49^2~5^2~1 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e67b77c791ca2778198c9e7088f3266ed2da7a55;p=pandora-kernel.git blk-flush: move the queue kick into A dm-multipath user reported[1] a problem when trying to boot a kernel with commit 4853abaae7e4a2af938115ce9071ef8684fb7af4 (block: fix flush machinery for stacking drivers with differring flush flags) applied. It turns out that an empty flush request can be sent into blk_insert_flush. When the BUG_ON was fixed to allow for this, I/O on the underlying device would stall. The reason is that blk_insert_cloned_request does not kick the queue. In the aforementioned commit, I had added a special case to kick the queue if data was sent down but the queue flags did not require a flush. A better solution is to push the queue kick up into blk_insert_cloned_request. This patch, along with a follow-on which fixes the BUG_ON, fixes the issue reported. [1] http://www.redhat.com/archives/dm-devel/2011-September/msg00154.html Reported-by: Christophe Saout Signed-off-by: Jeff Moyer Acked-by: Tejun Heo Stable note: 3.1 Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe --- Reading git-diff-tree failed