Patch "xen-blkfront: don't add indirect pages to list when" has been added to the 3.14-stable tree

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

xen-blkfront: don't add indirect pages to list when

to the 3.14-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:
xen-blkfront-don-t-add-indirect-pages-to-list-when.patch
and it can be found in the queue-3.14 subdirectory.

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

From: Bob Liu <[email protected]>
Date: Wed, 22 Jul 2015 14:40:09 +0800
Subject: xen-blkfront: don't add indirect pages to list when
!feature_persistent
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From: Bob Liu <[email protected]>

commit 7b0767502b5db11cb1f0daef2d01f6d71b1192dc upstream.

We should consider info->feature_persistent when adding indirect page to list info->indirect_pages, else the BUG_ON() in blkif_free() would be triggered.

When we are using persistent grants the indirect_pages list should always be empty because blkfront has pre-allocated enough persistent pages to fill all requests on the ring.

---
 drivers/block/xen-blkfront.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

@@ -1093,8 +1093,10 @@ static void blkif_completion(struct blk_
 				 * Add the used indirect page back to the list of
 				 * available pages for indirect grefs.
 				 */
-				indirect_page = pfn_to_page(s->indirect_grants[i]->pfn);
-				list_add(&indirect_page->lru, &info->indirect_pages);
+				if (!info->feature_persistent) {
+					indirect_page = pfn_to_page(s->indirect_grants[i]->pfn);
+					list_add(&indirect_page->lru, &info->indirect_pages);
+				}
 				s->indirect_grants[i]->gref = GRANT_INVALID_REF;
 				list_add_tail(&s->indirect_grants[i]->node, &info->grants);
 			}

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

queue-3.14/xen-blkfront-don-t-add-indirect-pages-to-list-when.patch