--- /dev/null
+From 6fb05e0dd32e566facb96ea61a48c7488daa5ac3 Mon Sep 17 00:00:00 2001
+From: Steven Toth <stoth@kernellabs.com>
+Date: Tue, 6 Jun 2017 09:30:27 -0300
+Subject: [media] saa7164: fix double fetch PCIe access condition
+
+From: Steven Toth <stoth@kernellabs.com>
+
+commit 6fb05e0dd32e566facb96ea61a48c7488daa5ac3 upstream.
+
+Avoid a double fetch by reusing the values from the prior transfer.
+
+Originally reported via https://bugzilla.kernel.org/show_bug.cgi?id=195559
+
+Thanks to Pengfei Wang <wpengfeinudt@gmail.com> for reporting.
+
+Signed-off-by: Steven Toth <stoth@kernellabs.com>
+Reported-by: Pengfei Wang <wpengfeinudt@gmail.com>
+Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
+Cc: Eduardo Valentin <eduval@amazon.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/media/pci/saa7164/saa7164-bus.c | 13 +------------
+ 1 file changed, 1 insertion(+), 12 deletions(-)
+
+--- a/drivers/media/pci/saa7164/saa7164-bus.c
++++ b/drivers/media/pci/saa7164/saa7164-bus.c
+@@ -389,11 +389,11 @@ int saa7164_bus_get(struct saa7164_dev *
+ msg_tmp.size = le16_to_cpu((__force __le16)msg_tmp.size);
+ msg_tmp.command = le32_to_cpu((__force __le32)msg_tmp.command);
+ msg_tmp.controlselector = le16_to_cpu((__force __le16)msg_tmp.controlselector);
++ memcpy(msg, &msg_tmp, sizeof(*msg));
+
+ /* No need to update the read positions, because this was a peek */
+ /* If the caller specifically want to peek, return */
+ if (peekonly) {
+- memcpy(msg, &msg_tmp, sizeof(*msg));
+ goto peekout;
+ }
+
+@@ -438,21 +438,15 @@ int saa7164_bus_get(struct saa7164_dev *
+ space_rem = bus->m_dwSizeGetRing - curr_grp;
+
+ if (space_rem < sizeof(*msg)) {
+- /* msg wraps around the ring */
+- memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, space_rem);
+- memcpy_fromio((u8 *)msg + space_rem, bus->m_pdwGetRing,
+- sizeof(*msg) - space_rem);
+ if (buf)
+ memcpy_fromio(buf, bus->m_pdwGetRing + sizeof(*msg) -
+ space_rem, buf_size);
+
+ } else if (space_rem == sizeof(*msg)) {
+- memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
+ if (buf)
+ memcpy_fromio(buf, bus->m_pdwGetRing, buf_size);
+ } else {
+ /* Additional data wraps around the ring */
+- memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
+ if (buf) {
+ memcpy_fromio(buf, bus->m_pdwGetRing + curr_grp +
+ sizeof(*msg), space_rem - sizeof(*msg));
+@@ -465,15 +459,10 @@ int saa7164_bus_get(struct saa7164_dev *
+
+ } else {
+ /* No wrapping */
+- memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
+ if (buf)
+ memcpy_fromio(buf, bus->m_pdwGetRing + curr_grp + sizeof(*msg),
+ buf_size);
+ }
+- /* Convert from little endian to CPU */
+- msg->size = le16_to_cpu((__force __le16)msg->size);
+- msg->command = le32_to_cpu((__force __le32)msg->command);
+- msg->controlselector = le16_to_cpu((__force __le16)msg->controlselector);
+
+ /* Update the read positions, adjusting the ring */
+ saa7164_writel(bus->m_dwGetReadPos, new_grp);