Patch "UBI: block: Add missing cache flushes" has been added to the 4.0-stable tree

This is a note to let you know that I've just added the patch titled

UBI: block: Add missing cache flushes

to the 4.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
ubi-block-add-missing-cache-flushes.patch
and it can be found in the queue-4.0 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Kevin Cernekee <[email protected]>
Date: Wed, 22 Apr 2015 09:30:53 -0300
Subject: UBI: block: Add missing cache flushes

From: Kevin Cernekee <[email protected]>

commit 98fb1ffd8154890d7051750e61ff5548c3ee2ab2 upstream.

Block drivers are responsible for calling flush_dcache_page() on each BIO request. This operation keeps the I$ coherent with the D$ on architectures that don't have hardware coherency support. Without this flush, random crashes are seen when executing user programs from an ext4 filesystem backed by a ubiblock device.

This patch is based on the change implemented in commit 2d4dc890b5c8 ("block: add helpers to run flush_dcache_page() against a bio and a request's pages").

---
 drivers/mtd/ubi/block.c |    2 ++
 1 file changed, 2 insertions(+)

@@ -310,6 +310,8 @@ static void ubiblock_do_work(struct work
 	blk_rq_map_sg(req->q, req, pdu->usgl.sg);
 
 	ret = ubiblock_read(pdu);
+	rq_flush_dcache_pages(req);
+
 	blk_mq_end_request(req, ret);
 }
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.0/ubi-block-add-missing-cache-flushes.patch