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=-6.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS 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 61B46C43381 for ; Sat, 23 Mar 2019 10:05:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2E9432196F for ; Sat, 23 Mar 2019 10:05:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="CgywDg93"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="CgywDg93" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727124AbfCWKF0 (ORCPT ); Sat, 23 Mar 2019 06:05:26 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:54246 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726014AbfCWKF0 (ORCPT ); Sat, 23 Mar 2019 06:05:26 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id C641060744; Sat, 23 Mar 2019 10:05:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1553335525; bh=pBdEEZubPvVz719nusovDIQoBewY7OeC40ze3oeECVc=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=CgywDg93c124f0WqbXTF9OjEszoU1DiYv8pxN3la4nRwDzKtLvIBZd9RSeUtrwC2T 7/nLv29rEzzu22ee+XBrq9u9bdm246oEzPXJ/l07hZlgJtSQ3gXIZoKVJ+lMcT5MO4 8LbBXwILhxZyhKpevSC70iaP4Gs18rczmmvHmO4g= Received: from [10.79.165.251] (blr-bdr-fw-01_globalnat_allzones-outside.qualcomm.com [103.229.18.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: mojha@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id CDF8D60A43; Sat, 23 Mar 2019 10:05:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1553335525; bh=pBdEEZubPvVz719nusovDIQoBewY7OeC40ze3oeECVc=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=CgywDg93c124f0WqbXTF9OjEszoU1DiYv8pxN3la4nRwDzKtLvIBZd9RSeUtrwC2T 7/nLv29rEzzu22ee+XBrq9u9bdm246oEzPXJ/l07hZlgJtSQ3gXIZoKVJ+lMcT5MO4 8LbBXwILhxZyhKpevSC70iaP4Gs18rczmmvHmO4g= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org CDF8D60A43 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=mojha@codeaurora.org Subject: Re: [PATCH] drm: vkms: check status of alloc_ordered_workqueue To: Kangjie Lu Cc: pakki001@umn.edu, Rodrigo Siqueira , Haneen Mohammed , Daniel Vetter , David Airlie , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org References: <20190309043628.6078-1-kjlu@umn.edu> From: Mukesh Ojha Message-ID: <955fbabe-e5f2-cfff-8dfd-1730243b0fff@codeaurora.org> Date: Sat, 23 Mar 2019 15:35:15 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.5.0 MIME-Version: 1.0 In-Reply-To: <20190309043628.6078-1-kjlu@umn.edu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/9/2019 10:06 AM, Kangjie Lu wrote: > alloc_ordered_workqueue may fail and return NULL. > The fix returns ENOMEM when it fails to avoid potential NULL > pointer dereference. > > Signed-off-by: Kangjie Lu > --- > drivers/gpu/drm/vkms/vkms_crtc.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c > index 8a9aeb0a9ea8..bb66dbcd5e3f 100644 > --- a/drivers/gpu/drm/vkms/vkms_crtc.c > +++ b/drivers/gpu/drm/vkms/vkms_crtc.c > @@ -219,6 +219,8 @@ int vkms_crtc_init(struct drm_device *dev, struct drm_crtc *crtc, > spin_lock_init(&vkms_out->state_lock); > > vkms_out->crc_workq = alloc_ordered_workqueue("vkms_crc_workq", 0); > + if (!vkms_out->crc_workq) > + return -ENOMEM; > > return ret; > } Check the clean up path more carefully, you have undo which you have done successfully in drm_crtc_init_with_planes. Thanks,  Mukesh