From patchwork Fri Mar 12 05:47:24 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kieran Bingham X-Patchwork-Id: 11556 X-Patchwork-Delegate: kieran.bingham@ideasonboard.com Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id 4072EBD1F1 for ; Fri, 12 Mar 2021 05:47:38 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id E2DF9605B2; Fri, 12 Mar 2021 06:47:37 +0100 (CET) Authentication-Results: lancelot.ideasonboard.com; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="NsrIm3ZV"; dkim-atps=neutral Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 3E29968C70 for ; Fri, 12 Mar 2021 06:47:33 +0100 (CET) Received: from localhost.localdomain (cpc89244-aztw30-2-0-cust3082.18-1.cable.virginm.net [86.31.172.11]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id D73BCA27; Fri, 12 Mar 2021 06:47:32 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1615528053; bh=+Nkpy6OrrmrW1e/H1IXCtKLtFskncsRslC13N7+Bok4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NsrIm3ZVkJFLuD2o5/sNdUOoOAbgqczqoWsLsSBNZSz1e2YgWmT8Nzu0SikhDe/n+ Oc5o1FPscriCOrbs8FhTlEqgiH8xVVUlX7kAKAFFk4DVa7WA7e9lUkZOv0SYCzYezu 2XxkluFhMX8x6KV04aYdE3t74KJQGsHswmJt64CA= From: Kieran Bingham To: libcamera devel Date: Fri, 12 Mar 2021 05:47:24 +0000 Message-Id: <20210312054727.852622-6-kieran.bingham@ideasonboard.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210312054727.852622-1-kieran.bingham@ideasonboard.com> References: <20210312054727.852622-1-kieran.bingham@ideasonboard.com> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v2 5/8] libcamera: v4l2_videodevice: Prevent queueing buffers without a cache X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" The v4l2 buffer cache allows us to map incoming buffers to an instance of the V4L2 Buffer required to actually queue. If the cache_ is not available, then the buffers required to allow queuing to a device have been released, and this indicates an issue at the pipeline handler. This could be a common mistake, as it could happen if a pipeline handler always requeues buffers to the device after they complete, without checking if they are cancelled. That can then lead to trying to queue a buffer to a device which no longer expects buffers, so add a loud message to indicate what has happened but return an error without fatally crashing. Signed-off-by: Kieran Bingham Reviewed-by: Jacopo Mondi Reviewed-by: Laurent Pinchart --- src/libcamera/v4l2_videodevice.cpp | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp index cb52d4cea3f6..12c09dc7578d 100644 --- a/src/libcamera/v4l2_videodevice.cpp +++ b/src/libcamera/v4l2_videodevice.cpp @@ -1391,6 +1391,16 @@ int V4L2VideoDevice::queueBuffer(FrameBuffer *buffer) struct v4l2_buffer buf = {}; int ret; + /* + * Pipeline handlers should not requeue buffers after releasing the + * buffers on the device. Any occurence of this error should be fixed + * in the pipeline handler directly. + */ + if (!cache_) { + LOG(V4L2, Fatal) << "No BufferCache available to queue."; + return -ENOENT; + } + ret = cache_->get(*buffer); if (ret < 0) return ret;