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=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, 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 22CFBC2F3A0 for ; Mon, 21 Jan 2019 14:30:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E554E20823 for ; Mon, 21 Jan 2019 14:30:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="iNng+F4A" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729402AbfAUOau (ORCPT ); Mon, 21 Jan 2019 09:30:50 -0500 Received: from fllv0016.ext.ti.com ([198.47.19.142]:48364 "EHLO fllv0016.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729036AbfAUOat (ORCPT ); Mon, 21 Jan 2019 09:30:49 -0500 Received: from fllv0035.itg.ti.com ([10.64.41.0]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id x0LEUcvW078902; Mon, 21 Jan 2019 08:30:38 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1548081038; bh=LofKKZaIxg/eNHhR3aW7yKb4VdXVlJz3p+laRi4U8q4=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=iNng+F4AK1HqBaX8KXdUG+E62X09NhA+j8ZKJISL09dyYEy0YUEJRp7i9v3bUGQH+ uhgWe96JDmX4RhC5yXPDivXhFdyywgI2QOiB5UoMAIquxExDIxga8ZykSlk6jfAoyg zvaVM0h/Mb1V/0xhVv7So7pRHKGXgyCD2oOYoXGM= Received: from DLEE103.ent.ti.com (dlee103.ent.ti.com [157.170.170.33]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x0LEUchw060682 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 21 Jan 2019 08:30:38 -0600 Received: from DLEE105.ent.ti.com (157.170.170.35) by DLEE103.ent.ti.com (157.170.170.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1591.10; Mon, 21 Jan 2019 08:30:37 -0600 Received: from dflp33.itg.ti.com (10.64.6.16) by DLEE105.ent.ti.com (157.170.170.35) with Microsoft SMTP Server (version=TLS1_0, cipher=TLS_RSA_WITH_AES_256_CBC_SHA) id 15.1.1591.10 via Frontend Transport; Mon, 21 Jan 2019 08:30:37 -0600 Received: from [172.22.75.231] (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp33.itg.ti.com (8.14.3/8.13.8) with ESMTP id x0LEUbJa028006; Mon, 21 Jan 2019 08:30:37 -0600 Subject: Re: [PATCH 11/14] staging: android: ion: Allow heap name to be null To: Laura Abbott , Brian Starkey CC: Sumit Semwal , Greg Kroah-Hartman , =?UTF-8?Q?Arve_Hj=c3=b8nnev=c3=a5g?= , "devel@driverdev.osuosl.org" , "linux-kernel@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , nd References: <20190111180523.27862-1-afd@ti.com> <20190111180523.27862-12-afd@ti.com> <20190116152807.phyq5pqrmbkj6oxk@DESKTOP-E1NTVVP.localdomain> <39453e0a-2db8-3a59-1909-e02caa9afa31@ti.com> <042dd3b1-9a41-2a76-270d-1c992d782c40@redhat.com> From: "Andrew F. Davis" Message-ID: <5c8fecd6-e8d5-127f-8271-8f91d8bfeb49@ti.com> Date: Mon, 21 Jan 2019 08:30:37 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <042dd3b1-9a41-2a76-270d-1c992d782c40@redhat.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 1/18/19 1:53 PM, Laura Abbott wrote: > On 1/16/19 9:12 AM, Andrew F. Davis wrote: >> On 1/16/19 9:28 AM, Brian Starkey wrote: >>> Hi Andrew, >>> >>> On Fri, Jan 11, 2019 at 12:05:20PM -0600, Andrew F. Davis wrote: >>>> The heap name can be used for debugging but otherwise does not seem >>>> to be required and no other part of the code will fail if left NULL >>>> except here. We can make it required and check for it at some point, >>>> for now lets just prevent this from causing a NULL pointer exception. >>> >>> I'm not so keen on this one. In the "new" API with heap querying, the >>> name string is the only way to identify the heap. I think Laura >>> mentioned at XDC2017 that it was expected that userspace should use >>> the strings to find the heap they want. >>> >> >> Right now the names are only for debug. I accidentally left the name >> null once and got a kernel crash. This is the only spot where it is >> needed so I fixed it up. The other option is to make the name mandatory >> and properly error out, I don't want to do that right now until the >> below discussion is had to see if names really do matter or not. >> > > Yes, the heap names are part of the query API and are the expected > way to identify individual heaps for the API at the moment so having > a null heap name is incorrect. The heap name seemed like the best way > to identify heaps to userspace but if you have an alternative proposal > I'd be interested. > Not sure I have a better proposal right now, I'll re-work this patch to force heap names to be populated before ion_device_add_heap() instead. (do you think that function name is now is a misnomer? how do you feel about renaming that to just ion_add_heap()?) Andrew > Thanks, > Laura > >> > >