From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5B945C433E2 for ; Tue, 15 Sep 2020 23:31:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0649B2193E for ; Tue, 15 Sep 2020 23:31:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="b7CmHkzj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727423AbgIOXbl (ORCPT ); Tue, 15 Sep 2020 19:31:41 -0400 Received: from perceval.ideasonboard.com ([213.167.242.64]:42862 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727384AbgIOXag (ORCPT ); Tue, 15 Sep 2020 19:30:36 -0400 Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id EA529FD8; Wed, 16 Sep 2020 01:30:33 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1600212634; bh=zIzDuf1sKDcdjxVaHFr72m3U6IU/kzjy98ujrCuNe7U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=b7CmHkzjWKj408c2UdMQbTaLVvuS79BYfLqrvLwNuYCVUHZqyvwLEpbE4+k2KJjDt 85IoaKvkbNXPZn5Fo2fj3aC98878mMGPd0H6Uj1R496lar6TB2PLjJR0xQ6a4KAtdN wwQj3z+JNadelAFPbOgMzZSI83h8HyJVA159mHv4= Date: Wed, 16 Sep 2020 02:30:04 +0300 From: Laurent Pinchart To: Yu Kuai Cc: kieran.bingham+renesas@ideasonboard.com, airlied@linux.ie, daniel@ffwll.ch, dri-devel@lists.freedesktop.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, yi.zhang@huawei.com Subject: Re: [PATCH] drm: rcar-du: add missing put_device() call in rcar_du_vsp_init() Message-ID: <20200915233004.GD14954@pendragon.ideasonboard.com> References: <20200910132354.692397-1-yukuai3@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200910132354.692397-1-yukuai3@huawei.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Yu, Thank you for the patch. On Thu, Sep 10, 2020 at 09:23:54PM +0800, Yu Kuai wrote: > if of_find_device_by_node() succeed, rcar_du_vsp_init() doesn't have > a corresponding put_device(). Thus add a jump target to fix the exception > handling for this function implementation. > > Fixes: 6d62ef3ac30b ("drm: rcar-du: Expose the VSP1 compositor through KMS planes") > Signed-off-by: Yu Kuai > --- > drivers/gpu/drm/rcar-du/rcar_du_vsp.c | 19 +++++++++++++------ > 1 file changed, 13 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/rcar-du/rcar_du_vsp.c b/drivers/gpu/drm/rcar-du/rcar_du_vsp.c > index f1a81c9b184d..172ee3f3b21c 100644 > --- a/drivers/gpu/drm/rcar-du/rcar_du_vsp.c > +++ b/drivers/gpu/drm/rcar-du/rcar_du_vsp.c > @@ -352,14 +352,16 @@ int rcar_du_vsp_init(struct rcar_du_vsp *vsp, struct device_node *np, > > /* Find the VSP device and initialize it. */ > pdev = of_find_device_by_node(np); > - if (!pdev) > - return -ENXIO; > + if (!pdev) { > + ret = -ENXIO; > + goto put_device; > + } This change isn't needed, and will actually cause a crash, as pdev is NULL. > > vsp->vsp = &pdev->dev; > > ret = vsp1_du_init(vsp->vsp); > if (ret < 0) > - return ret; > + goto put_device; > > /* > * The VSP2D (Gen3) has 5 RPFs, but the VSP1D (Gen2) is limited to > @@ -369,8 +371,10 @@ int rcar_du_vsp_init(struct rcar_du_vsp *vsp, struct device_node *np, > > vsp->planes = devm_kcalloc(rcdu->dev, vsp->num_planes, > sizeof(*vsp->planes), GFP_KERNEL); > - if (!vsp->planes) > - return -ENOMEM; > + if (!vsp->planes) { > + ret = -ENOMEM; > + goto put_device; > + } > > for (i = 0; i < vsp->num_planes; ++i) { > enum drm_plane_type type = i < num_crtcs > @@ -387,7 +391,7 @@ int rcar_du_vsp_init(struct rcar_du_vsp *vsp, struct device_node *np, > ARRAY_SIZE(rcar_du_vsp_formats), > NULL, type, NULL); > if (ret < 0) > - return ret; > + goto put_device; > > drm_plane_helper_add(&plane->plane, > &rcar_du_vsp_plane_helper_funcs); > @@ -403,4 +407,7 @@ int rcar_du_vsp_init(struct rcar_du_vsp *vsp, struct device_node *np, > } > > return 0; I would add a blank line here. > +put_device: And maybe name the label "error" ? > + put_device(&pdev->dev); > + return ret; > } We need more than this, we also need to call put_device() when the driver is unloaded. The way to handle cleanup in DRM is through drmm_add_action() nowadays, and I think we could thus simply replace the change above with a cleanup action that is run both in the error path and at driver remove. I'll post a proposal in a reply to this e-mail. -- Regards, Laurent Pinchart