[patch] virtio: silence uninitialized variable warnings

[patch] virtio: silence uninitialized variable warnings

[Dan Carpenter]

Most ->get() functions seem to call BUG_ON() if offset + len is out of
range, but rproc_virtio_get() returns early without initializing ret.
Presumably it can't actually happen but it leads to a static checker
warning.  Let's just initialize "ret".

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 6e6cb0c9..597dbef 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -334,7 +334,7 @@ static inline void virtio_cread_bytes(struct virtio_device *vdev,
 
 static inline u8 virtio_cread8(struct virtio_device *vdev, unsigned int offset)
 {
-	u8 ret;
+	u8 ret = 0;
 	vdev->config->get(vdev, offset, &ret, sizeof(ret));
 	return ret;
 }
@@ -348,7 +348,7 @@ static inline void virtio_cwrite8(struct virtio_device *vdev,
 static inline u16 virtio_cread16(struct virtio_device *vdev,
 				 unsigned int offset)
 {
-	u16 ret;
+	u16 ret = 0;
 	vdev->config->get(vdev, offset, &ret, sizeof(ret));
 	return virtio16_to_cpu(vdev, (__force __virtio16)ret);
 }
@@ -363,7 +363,7 @@ static inline void virtio_cwrite16(struct virtio_device *vdev,
 static inline u32 virtio_cread32(struct virtio_device *vdev,
 				 unsigned int offset)
 {
-	u32 ret;
+	u32 ret = 0;
 	vdev->config->get(vdev, offset, &ret, sizeof(ret));
 	return virtio32_to_cpu(vdev, (__force __virtio32)ret);
 }
@@ -378,7 +378,7 @@ static inline void virtio_cwrite32(struct virtio_device *vdev,
 static inline u64 virtio_cread64(struct virtio_device *vdev,
 				 unsigned int offset)
 {
-	u64 ret;
+	u64 ret = 0;
 	__virtio_cread_many(vdev, offset, &ret, 1, sizeof(ret));
 	return virtio64_to_cpu(vdev, (__force __virtio64)ret);
 }

[patch] virtio: Silence uninitialized variable warning

[Dan Carpenter]

Smatch complains that we might not initialize "queue".  The issue is
callers like setup_vq() from virtio_pci_modern.c where "num" could be
something like 2 and "vring_align" is 64.  In that case, vring_size() is
less than PAGE_SIZE.  It won't happen in real life, but we're getting
the value of "num" from a register so it's not really possible to tell
what value it holds with static analysis.

Let's just silence the warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 5c802d4..ca6bfdd 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1006,7 +1006,7 @@ struct virtqueue *vring_create_virtqueue(
 	const char *name)
 {
 	struct virtqueue *vq;
-	void *queue;
+	void *queue = NULL;
 	dma_addr_t dma_addr;
 	size_t queue_size_in_bytes;
 	struct vring vring;