[libcamera-devel] [PATCH 01/10] libcamera: pipeline: Fix double release of media devices

[Laurent Pinchart]

Media devices are acquired in the match() function of pipeline handlers,
and explicitly released if no match is found. The pipeline handler is
then deleted, which causes a second release of the media device in the
destructor. Fix this by removing the explicit release in the match()
function.

Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
 src/libcamera/pipeline/ipu3/ipu3.cpp | 28 +++++++++++-----------------
 src/libcamera/pipeline/uvcvideo.cpp  |  1 -
 src/libcamera/pipeline/vimc.cpp      |  5 +----
 3 files changed, 12 insertions(+), 22 deletions(-)

diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp
index 9694d0ce51ab..cf5c28577393 100644
--- a/src/libcamera/pipeline/ipu3/ipu3.cpp
+++ b/src/libcamera/pipeline/ipu3/ipu3.cpp
@@ -278,19 +278,20 @@ bool PipelineHandlerIPU3::match(DeviceEnumerator *enumerator)
 	imgu_dm.add("ipu3-imgu 1 viewfinder");
 	imgu_dm.add("ipu3-imgu 1 3a stat");
 
+	/*
+	 * It is safe to acquire both media devices at this point as
+	 * DeviceEnumerator::search() skips the busy ones for us.
+	 */
 	cio2_ = enumerator->search(cio2_dm);
 	if (!cio2_)
 		return false;
 
+	cio2_->acquire();
+
 	imgu_ = enumerator->search(imgu_dm);
 	if (!imgu_)
 		return false;
 
-	/*
-	 * It is safe to acquire both media devices at this point as
-	 * DeviceEnumerator::search() skips the busy ones for us.
-	 */
-	cio2_->acquire();
 	imgu_->acquire();
 
 	/*
@@ -301,25 +302,18 @@ bool PipelineHandlerIPU3::match(DeviceEnumerator *enumerator)
 	 * not need to be changed after.
 	 */
 	if (cio2_->open())
-		goto error_release_mdev;
+		return false;
 
-	if (cio2_->disableLinks())
-		goto error_close_cio2;
+	if (cio2_->disableLinks()) {
+		cio2_->close();
+		return false;
+	}
 
 	registerCameras();
 
 	cio2_->close();
 
 	return true;
-
-error_close_cio2:
-	cio2_->close();
-
-error_release_mdev:
-	cio2_->release();
-	imgu_->release();
-
-	return false;
 }
 
 /*
diff --git a/src/libcamera/pipeline/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo.cpp
index b7b8ff109109..dd20bb085a29 100644
--- a/src/libcamera/pipeline/uvcvideo.cpp
+++ b/src/libcamera/pipeline/uvcvideo.cpp
@@ -167,7 +167,6 @@ bool PipelineHandlerUVC::match(DeviceEnumerator *enumerator)
 		if (!video_)
 			LOG(UVC, Error) << "Could not find a default video device";
 
-		media_->release();
 		return false;
 	}
 
diff --git a/src/libcamera/pipeline/vimc.cpp b/src/libcamera/pipeline/vimc.cpp
index 812777cffbb3..640fca5cb0e7 100644
--- a/src/libcamera/pipeline/vimc.cpp
+++ b/src/libcamera/pipeline/vimc.cpp
@@ -165,11 +165,8 @@ bool PipelineHandlerVimc::match(DeviceEnumerator *enumerator)
 	media_->acquire();
 
 	video_ = new V4L2Device(media_->getEntityByName("Raw Capture 1"));
-
-	if (video_->open()) {
-		media_->release();
+	if (video_->open())
 		return false;
-	}
 
 	std::vector<Stream *> streams{ &stream_ };
 	std::shared_ptr<Camera> camera = Camera::create(this, "VIMC Sensor B",
-- 
Regards,

Laurent Pinchart