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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 83CB6C433DB for ; Mon, 18 Jan 2021 10:18:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3CDBA22228 for ; Mon, 18 Jan 2021 10:18:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389742AbhARKMv (ORCPT ); Mon, 18 Jan 2021 05:12:51 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49170 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389177AbhARJop (ORCPT ); Mon, 18 Jan 2021 04:44:45 -0500 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 16F8FC061573; Mon, 18 Jan 2021 01:44:05 -0800 (PST) Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 6DB092BB; Mon, 18 Jan 2021 10:44:03 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1610963043; bh=xxk+lHswU9GlVNAzi20vlKRav8h21hAOnc3sgblTiI0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GfDVi4uOmKDP4tvYUwfaXmm9qFwbo13a2g19YNpayVOme+gSnX1h+XsReQbiQkAIZ /ybBeCnZDJMG2EIL4aM8+v7jxOkw9cTc3nqeS+0tRvYNLF9fWqUK3bAdnwx5Q8US7E hCRN4K0l/UvsWd8MdYfweJqCJLUttELffGps90J8= Date: Mon, 18 Jan 2021 11:43:47 +0200 From: Laurent Pinchart To: Paul Cercueil Cc: David Airlie , Daniel Vetter , linux-kernel@vger.kernel.org, stable@vger.kernel.org, od@zcrc.me, dri-devel@lists.freedesktop.org, Sam Ravnborg Subject: Re: [PATCH 2/3] drm/ingenic: Register devm action to cleanup encoders Message-ID: References: <20210117112646.98353-1-paul@crapouillou.net> <20210117112646.98353-3-paul@crapouillou.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210117112646.98353-3-paul@crapouillou.net> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Paul, Thank you for the patch. On Sun, Jan 17, 2021 at 11:26:45AM +0000, Paul Cercueil wrote: > Since the encoders have been devm-allocated, they will be freed way > before drm_mode_config_cleanup() is called. To avoid use-after-free > conditions, we then must ensure that drm_encoder_cleanup() is called > before the encoders are freed. How about allocating the encoder with drmm_encoder_alloc() instead ? > Fixes: c369cb27c267 ("drm/ingenic: Support multiple panels/bridges") > Cc: # 5.8+ > Signed-off-by: Paul Cercueil > --- > drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > index 368bfef8b340..d23a3292a0e0 100644 > --- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > +++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c > @@ -803,6 +803,11 @@ static void __maybe_unused ingenic_drm_release_rmem(void *d) > of_reserved_mem_device_release(d); > } > > +static void ingenic_drm_encoder_cleanup(void *encoder) > +{ > + drm_encoder_cleanup(encoder); > +} > + > static int ingenic_drm_bind(struct device *dev, bool has_components) > { > struct platform_device *pdev = to_platform_device(dev); > @@ -1011,6 +1016,11 @@ static int ingenic_drm_bind(struct device *dev, bool has_components) > return ret; > } > > + ret = devm_add_action_or_reset(dev, ingenic_drm_encoder_cleanup, > + encoder); > + if (ret) > + return ret; > + > ret = drm_bridge_attach(encoder, bridge, NULL, 0); > if (ret) { > dev_err(dev, "Unable to attach bridge\n"); -- Regards, Laurent Pinchart