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=-8.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_MUTT 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 948A5C43381 for ; Mon, 25 Mar 2019 08:31:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC8DE2085A for ; Mon, 25 Mar 2019 08:31:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="iyW1VlzL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730069AbfCYIbY (ORCPT ); Mon, 25 Mar 2019 04:31:24 -0400 Received: from mail-ed1-f67.google.com ([209.85.208.67]:41659 "EHLO mail-ed1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729823AbfCYIbY (ORCPT ); Mon, 25 Mar 2019 04:31:24 -0400 Received: by mail-ed1-f67.google.com with SMTP id a25so6694806edc.8 for ; Mon, 25 Mar 2019 01:31:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=sender:date:from:to:cc:subject:message-id:mail-followup-to :references:mime-version:content-disposition:in-reply-to:user-agent; bh=ZFjyvS17Z6wm20BxdnVTcZ5fFz/Oo19fffMdiwpVX+E=; b=iyW1VlzLnyb+08UN38l/cp3dWfmmjSiRoc8dJQCH6u3FrTlsP/PEOYPUXPdb11RHfE dN20v5ftAfXaP7/3DK3zgZQP5FPXTAGwoEJGFfpmXyNFD1okYUUrWdn/+Bg2J3wXTNQs 4rqJgkqFbBcVF1hLuGFZxNDNJ4pzGQTsiTF7k= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :mail-followup-to:references:mime-version:content-disposition :in-reply-to:user-agent; bh=ZFjyvS17Z6wm20BxdnVTcZ5fFz/Oo19fffMdiwpVX+E=; b=tQZUeuAtmE4zkrUCYX9t8/fS1jJFrFS2Ocka5626ICc7H88wBHU6cCV7YnIJILYwSe fsEJkkSvkAqGDU54zjF/tXmXw6CCrl3UYsi03AQedt534mbMLVkj5Ere5VcGa+yr2r3n nO/tTqIqnVeNvadJYjGV02+B+woW07Q6uP9WmcZSQMF7WnkaWLdTsWv2RGF22ZzzEhEe UgMCHTt1S+t541GyWryG1V/7hyy9hUro7LIxWYIe9nEO72nZLqz/hk8OdoIxEKMyC1Vd nkjQTH9Kl3SWP8wMt4Bk5pR6i77uh/5SMop8n10jblrcvauUWJN3VxeNNQmSsOZEwmie AfYg== X-Gm-Message-State: APjAAAUMLp5TLQP0N2DlAx8xv68HY1KTXhdCHuHo3SiHyt1CT9dPhH60 kerv/gZsL6L9Eg++Eoz1p1C48A== X-Google-Smtp-Source: APXvYqylyWTMDdci9ny1J/iGd5MQVw9ZaSf24SZqE88bERgwzciaIjRaHa344CkBcbIGfJescifz4w== X-Received: by 2002:a50:9485:: with SMTP id s5mr15029498eda.223.1553502682378; Mon, 25 Mar 2019 01:31:22 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:569e:0:3106:d637:d723:e855]) by smtp.gmail.com with ESMTPSA id s20sm529289edb.57.2019.03.25.01.31.20 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 25 Mar 2019 01:31:21 -0700 (PDT) Date: Mon, 25 Mar 2019 09:31:19 +0100 From: Daniel Vetter 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 Subject: Re: [PATCH v2] drm: vkms: check status of alloc_ordered_workqueue Message-ID: <20190325083119.GB2665@phenom.ffwll.local> Mail-Followup-To: Kangjie Lu , pakki001@umn.edu, Rodrigo Siqueira , Haneen Mohammed , David Airlie , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org References: <955fbabe-e5f2-cfff-8dfd-1730243b0fff@codeaurora.org> <20190323214216.10824-1-kjlu@umn.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190323214216.10824-1-kjlu@umn.edu> X-Operating-System: Linux phenom 4.19.0-1-amd64 User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 23, 2019 at 04:42:16PM -0500, Kangjie Lu wrote: > alloc_ordered_workqueue may fail and return NULL. > The fix cleans up drm plans and returns ENOMEM when it fails to > avoid potential NULL pointer dereference. > > Signed-off-by: Kangjie Lu > --- > V2: clean up resources > --- > drivers/gpu/drm/vkms/vkms_crtc.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c > index 8a9aeb0a9ea8..018b52dd953a 100644 > --- a/drivers/gpu/drm/vkms/vkms_crtc.c > +++ b/drivers/gpu/drm/vkms/vkms_crtc.c > @@ -219,6 +219,17 @@ 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) { > + ret = -ENOMEM; > + goto cleanup; > + } > + > + return ret; > > +cleanup: Style nit for the future, for clarity I'd label this err:, since this path is only taken for failures, and not to do cleanup for all cases. Aside from that, I think your v1 was correct, vkms_crtc_init only sets up the crtc, it doesn't allocate the cursor/planes. That's done from vkms_output_init, which already has the cleanup code to handle this case. -Daniel > + if (!IS_ERR_OR_NULL(cursor)) > + drm_plane_cleanup(cursor); > + if (!IS_ERR(primary)) > + drm_plane_cleanup(primary); > return ret; > } > -- > 2.17.1 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch