Re: [PATCH 03/10] drm/virtio: fix lock context imbalance

[Jason Wang]

On 2016年12月06日 23:40, Michael S. Tsirkin wrote:

When virtio_gpu_free_vbufs exits due to list empty, it does not
drop the free_vbufs lock that it took.
list empty is not expected to happen anyway, but it can't hurt to fix
this and drop the lock.

Signed-off-by: Michael S. Tsirkin 
---
  drivers/gpu/drm/virtio/virtgpu_vq.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)


Reviewed-by: Jason Wang 



diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c 
b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 5a0f8a7..2f0c2f9 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -109,8 +109,10 @@ void virtio_gpu_free_vbufs(struct virtio_gpu_device *vgdev)
  
  	spin_lock(>free_vbufs_lock);

for (i = 0; i < count; i++) {
-   if (WARN_ON(list_empty(>free_vbufs)))
+   if (WARN_ON(list_empty(>free_vbufs))) {
+   spin_unlock(>free_vbufs_lock);
return;
+   }
vbuf = list_first_entry(>free_vbufs,
struct virtio_gpu_vbuffer, list);
list_del(>list);

Re: [PATCH 03/10] drm/virtio: fix lock context imbalance

[Jason Wang]

On 2016年12月06日 23:40, Michael S. Tsirkin wrote:

When virtio_gpu_free_vbufs exits due to list empty, it does not
drop the free_vbufs lock that it took.
list empty is not expected to happen anyway, but it can't hurt to fix
this and drop the lock.

Signed-off-by: Michael S. Tsirkin 
---
  drivers/gpu/drm/virtio/virtgpu_vq.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)


Reviewed-by: Jason Wang 



diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c 
b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 5a0f8a7..2f0c2f9 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -109,8 +109,10 @@ void virtio_gpu_free_vbufs(struct virtio_gpu_device *vgdev)
  
  	spin_lock(>free_vbufs_lock);

for (i = 0; i < count; i++) {
-   if (WARN_ON(list_empty(>free_vbufs)))
+   if (WARN_ON(list_empty(>free_vbufs))) {
+   spin_unlock(>free_vbufs_lock);
return;
+   }
vbuf = list_first_entry(>free_vbufs,
struct virtio_gpu_vbuffer, list);
list_del(>list);

[PATCH 03/10] drm/virtio: fix lock context imbalance

[Michael S. Tsirkin]

When virtio_gpu_free_vbufs exits due to list empty, it does not
drop the free_vbufs lock that it took.
list empty is not expected to happen anyway, but it can't hurt to fix
this and drop the lock.

Signed-off-by: Michael S. Tsirkin 
---
 drivers/gpu/drm/virtio/virtgpu_vq.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c 
b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 5a0f8a7..2f0c2f9 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -109,8 +109,10 @@ void virtio_gpu_free_vbufs(struct virtio_gpu_device *vgdev)
 
spin_lock(>free_vbufs_lock);
for (i = 0; i < count; i++) {
-   if (WARN_ON(list_empty(>free_vbufs)))
+   if (WARN_ON(list_empty(>free_vbufs))) {
+   spin_unlock(>free_vbufs_lock);
return;
+   }
vbuf = list_first_entry(>free_vbufs,
struct virtio_gpu_vbuffer, list);
list_del(>list);
-- 
MST

[PATCH 03/10] drm/virtio: fix lock context imbalance

[Michael S. Tsirkin]

When virtio_gpu_free_vbufs exits due to list empty, it does not
drop the free_vbufs lock that it took.
list empty is not expected to happen anyway, but it can't hurt to fix
this and drop the lock.

Signed-off-by: Michael S. Tsirkin 
---
 drivers/gpu/drm/virtio/virtgpu_vq.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c 
b/drivers/gpu/drm/virtio/virtgpu_vq.c
index 5a0f8a7..2f0c2f9 100644
--- a/drivers/gpu/drm/virtio/virtgpu_vq.c
+++ b/drivers/gpu/drm/virtio/virtgpu_vq.c
@@ -109,8 +109,10 @@ void virtio_gpu_free_vbufs(struct virtio_gpu_device *vgdev)
 
spin_lock(>free_vbufs_lock);
for (i = 0; i < count; i++) {
-   if (WARN_ON(list_empty(>free_vbufs)))
+   if (WARN_ON(list_empty(>free_vbufs))) {
+   spin_unlock(>free_vbufs_lock);
return;
+   }
vbuf = list_first_entry(>free_vbufs,
struct virtio_gpu_vbuffer, list);
list_del(>list);
-- 
MST