Among other potential issues, this fixes a race between output polling
and status_show() that could cause a load detection false positive
with the nouveau driver.
Signed-off-by: Francisco Jerez <currojerez at riseup.net>
---
drivers/gpu/drm/drm_sysfs.c | 71 ++++++++++++++++++++++++++++---------------
1 files changed, 46 insertions(+), 25 deletions(-)
diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
index 85da4c4..25a9d9e 100644
--- a/drivers/gpu/drm/drm_sysfs.c
+++ b/drivers/gpu/drm/drm_sysfs.c
@@ -157,9 +157,13 @@ static ssize_t status_show(struct device *device,
char *buf)
{
struct drm_connector *connector = to_drm_connector(device);
+ struct drm_device *dev = connector->dev;
enum drm_connector_status status;
+ mutex_lock(&dev->mode_config.mutex);
status = connector->funcs->detect(connector, true);
+ mutex_unlock(&dev->mode_config.mutex);
+
return snprintf(buf, PAGE_SIZE, "%s\n",
drm_get_connector_status_name(status));
}
@@ -173,9 +177,11 @@ static ssize_t dpms_show(struct device *device,
uint64_t dpms_status;
int ret;
+ mutex_lock(&dev->mode_config.mutex);
ret = drm_connector_property_get_value(connector,
dev->mode_config.dpms_property,
&dpms_status);
+ mutex_unlock(&dev->mode_config.mutex);
if (ret)
return 0;
@@ -199,25 +205,27 @@ static ssize_t edid_show(struct file *filp, struct
kobject *kobj,
{
struct device *connector_dev = container_of(kobj, struct device, kobj);
struct drm_connector *connector = to_drm_connector(connector_dev);
+ struct drm_device *dev = connector->dev;
unsigned char *edid;
- size_t size;
+ size_t size, n = 0;
+ mutex_lock(&dev->mode_config.mutex);
if (!connector->edid_blob_ptr)
- return 0;
+ goto out;
edid = connector->edid_blob_ptr->data;
size = connector->edid_blob_ptr->length;
if (!edid)
- return 0;
+ goto out;
if (off >= size)
- return 0;
-
- if (off + count > size)
- count = size - off;
- memcpy(buf, edid + off, count);
+ goto out;
- return count;
+ n = min(count, size - (size_t)off);
+ memcpy(buf, edid + off, n);
+out:
+ mutex_unlock(&dev->mode_config.mutex);
+ return n;
}
static ssize_t modes_show(struct device *device,
@@ -225,13 +233,16 @@ static ssize_t modes_show(struct device *device,
char *buf)
{
struct drm_connector *connector = to_drm_connector(device);
+ struct drm_device *dev = connector->dev;
struct drm_display_mode *mode;
int written = 0;
+ mutex_lock(&dev->mode_config.mutex);
list_for_each_entry(mode, &connector->modes, head) {
written += snprintf(buf + written, PAGE_SIZE - written, "%s\n",
mode->name);
}
+ mutex_unlock(&dev->mode_config.mutex);
return written;
}
@@ -245,7 +256,9 @@ static ssize_t subconnector_show(struct device *device,
struct drm_property *prop = NULL;
uint64_t subconnector;
int is_tv = 0;
- int ret;
+ int ret = 0;
+
+ mutex_lock(&dev->mode_config.mutex);
switch (connector->connector_type) {
case DRM_MODE_CONNECTOR_DVII:
@@ -260,21 +273,24 @@ static ssize_t subconnector_show(struct device *device,
break;
default:
DRM_ERROR("Wrong connector type for this property\n");
- return 0;
+ goto out;
}
if (!prop) {
DRM_ERROR("Unable to find subconnector property\n");
- return 0;
+ goto out;
}
ret = drm_connector_property_get_value(connector, prop, &subconnector);
if (ret)
- return 0;
+ goto out;
- return snprintf(buf, PAGE_SIZE, "%s", is_tv ?
- drm_get_tv_subconnector_name((int)subconnector) :
- drm_get_dvi_i_subconnector_name((int)subconnector));
+ ret = snprintf(buf, PAGE_SIZE, "%s", is_tv ?
+ drm_get_tv_subconnector_name((int)subconnector) :
+ drm_get_dvi_i_subconnector_name((int)subconnector));
+out:
+ mutex_unlock(&dev->mode_config.mutex);
+ return ret;
}
static ssize_t select_subconnector_show(struct device *device,
@@ -286,7 +302,9 @@ static ssize_t select_subconnector_show(struct device
*device,
struct drm_property *prop = NULL;
uint64_t subconnector;
int is_tv = 0;
- int ret;
+ int ret = 0;
+
+ mutex_lock(&dev->mode_config.mutex);
switch (connector->connector_type) {
case DRM_MODE_CONNECTOR_DVII:
@@ -301,21 +319,24 @@ static ssize_t select_subconnector_show(struct device
*device,
break;
default:
DRM_ERROR("Wrong connector type for this property\n");
- return 0;
+ goto out;
}
if (!prop) {
DRM_ERROR("Unable to find select subconnector property\n");
- return 0;
+ goto out;
}
ret = drm_connector_property_get_value(connector, prop, &subconnector);
if (ret)
- return 0;
+ goto out;
- return snprintf(buf, PAGE_SIZE, "%s", is_tv ?
- drm_get_tv_select_name((int)subconnector) :
- drm_get_dvi_i_select_name((int)subconnector));
+ ret = snprintf(buf, PAGE_SIZE, "%s", is_tv ?
+ drm_get_tv_select_name((int)subconnector) :
+ drm_get_dvi_i_select_name((int)subconnector));
+out:
+ mutex_unlock(&dev->mode_config.mutex);
+ return ret;
}
static struct device_attribute connector_attrs[] = {
--
1.6.4.4
