1 files changed, 0 insertions, 41 deletions
diff --git a/system/xen/patches/xsa155-xen-0003-libvchan-Read-prod-cons-only-once.patch b/system/xen/patches/xsa155-xen-0003-libvchan-Read-prod-cons-only-once.patch
deleted file mode 100644
index 56a6e538f4..0000000000
--- a/system/xen/patches/xsa155-xen-0003-libvchan-Read-prod-cons-only-once.patch
+++ /dev/null
@@ -1,41 +0,0 @@
-From c1fce65e2b720684ea6ba76ae59921542bd154bb Mon Sep 17 00:00:00 2001
-From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
-Date: Fri, 20 Nov 2015 12:22:14 -0500
-Subject: [PATCH 3/3] libvchan: Read prod/cons only once.
-
-We must ensure that the prod/cons are only read once and that
-the compiler won't try to optimize the reads. That is split
-the read of these in multiple instructions influencing later
-branch code. As such insert barriers when fetching the cons
-and prod index.
-
-This is part of XSA155.
-
-Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
----
- tools/libvchan/io.c | 2 ++
- 1 file changed, 2 insertions(+)
-
-diff --git a/tools/libvchan/io.c b/tools/libvchan/io.c
-index 8a9629b..381cc05 100644
---- a/tools/libvchan/io.c
-+++ b/tools/libvchan/io.c
-@@ -117,6 +117,7 @@ static inline int send_notify(struct libxenvchan *ctrl, uint8_t bit)
- static inline int raw_get_data_ready(struct libxenvchan *ctrl)
- {
- 	uint32_t ready = rd_prod(ctrl) - rd_cons(ctrl);
-+	xen_mb(); /* Ensure 'ready' is read only once. */
- 	if (ready > rd_ring_size(ctrl))
- 		/* We have no way to return errors.  Locking up the ring is
- 		 * better than the alternatives. */
-@@ -158,6 +159,7 @@ int libxenvchan_data_ready(struct libxenvchan *ctrl)
- static inline int raw_get_buffer_space(struct libxenvchan *ctrl)
- {
- 	uint32_t ready = wr_ring_size(ctrl) - (wr_prod(ctrl) - wr_cons(ctrl));
-+	xen_mb(); /* Ensure 'ready' is read only once. */
- 	if (ready > wr_ring_size(ctrl))
- 		/* We have no way to return errors.  Locking up the ring is
- 		 * better than the alternatives. */
--- 
-2.1.0
-