From: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Date: Mon, 28 Nov 2011 16:49:10 +0000 (-0500)
Subject: xen/gntalloc: release grant references on page free
X-Git-Tag: firefly_0821_release~3680^2~3781^2~21
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0105d2b4fbc24c2fb6ca9bae650784dd7ddf0b12;p=firefly-linux-kernel-4.4.55.git

xen/gntalloc: release grant references on page free

gnttab_end_foreign_access_ref does not return the grant reference it is
passed to the free list; gnttab_free_grant_reference needs to be
explicitly called. While gnttab_end_foreign_access provides a wrapper
for this, it is unsuitable because it does not return errors.

Reported-by: Anil Madhavapeddy <anil@recoil.org>
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---

diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c
index c95181f43a6a..f330a4b8b685 100644
--- a/drivers/xen/gntalloc.c
+++ b/drivers/xen/gntalloc.c
@@ -191,6 +191,8 @@ static void __del_gref(struct gntalloc_gref *gref)
 
 		if (!gnttab_end_foreign_access_ref(gref->gref_id, 0))
 			return;
+
+		gnttab_free_grant_reference(gref->gref_id);
 	}
 
 	gref_size--;