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authorDaniel Vetter <daniel.vetter@ffwll.ch>2015-06-22 09:31:59 +0200
committerDave Airlie <airlied@redhat.com>2015-06-23 02:23:50 +0200
commit9254ec496a1dbdddeab50021a8138dc627a8166a (patch)
tree22cdb39dd787146551e0f36ba6749e5cf7972a10 /drivers/gpu
parentMerge tag 'drm-intel-next-fixes-2015-06-22' of git://anongit.freedesktop.org/... (diff)
downloadlinux-9254ec496a1dbdddeab50021a8138dc627a8166a.tar.xz
linux-9254ec496a1dbdddeab50021a8138dc627a8166a.zip
drm/dp/mst: make sure mst_primary mstb is valid in work function
This validates the mst_primary under the lock, and then calls into the check and send function. This makes the code a lot easier to understand the locking rules in. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: stable@vger.kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers/gpu')
-rw-r--r--drivers/gpu/drm/drm_dp_mst_topology.c24
1 files changed, 19 insertions, 5 deletions
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 132581ca4ad8..1c9670665281 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -1189,7 +1189,7 @@ static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *m
struct drm_dp_mst_branch *mstb)
{
struct drm_dp_mst_port *port;
-
+ struct drm_dp_mst_branch *mstb_child;
if (!mstb->link_address_sent) {
drm_dp_send_link_address(mgr, mstb);
mstb->link_address_sent = true;
@@ -1204,17 +1204,31 @@ static void drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *m
if (!port->available_pbn)
drm_dp_send_enum_path_resources(mgr, mstb, port);
- if (port->mstb)
- drm_dp_check_and_send_link_address(mgr, port->mstb);
+ if (port->mstb) {
+ mstb_child = drm_dp_get_validated_mstb_ref(mgr, port->mstb);
+ if (mstb_child) {
+ drm_dp_check_and_send_link_address(mgr, mstb_child);
+ drm_dp_put_mst_branch_device(mstb_child);
+ }
+ }
}
}
static void drm_dp_mst_link_probe_work(struct work_struct *work)
{
struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work);
+ struct drm_dp_mst_branch *mstb;
- drm_dp_check_and_send_link_address(mgr, mgr->mst_primary);
-
+ mutex_lock(&mgr->lock);
+ mstb = mgr->mst_primary;
+ if (mstb) {
+ kref_get(&mstb->kref);
+ }
+ mutex_unlock(&mgr->lock);
+ if (mstb) {
+ drm_dp_check_and_send_link_address(mgr, mstb);
+ drm_dp_put_mst_branch_device(mstb);
+ }
}
static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr,