From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751001AbdJCVmh (ORCPT ); Tue, 3 Oct 2017 17:42:37 -0400 Received: from mail-qk0-f182.google.com ([209.85.220.182]:55544 "EHLO mail-qk0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750841AbdJCVmg (ORCPT ); Tue, 3 Oct 2017 17:42:36 -0400 X-Google-Smtp-Source: AOwi7QAGh4S9dxDJk77ni0F5yYazlKIe1ozu7uENq51SAi6kGXL2nhqqLKLsBkpNjwJYCwU8c2HaEg== Subject: Re: [PATCH v5 2/2] staging: ion: create one device entry per heap To: Mark Brown Cc: Benjamin Gaignard , sumit.semwal@linaro.org, gregkh@linuxfoundation.org, arve@android.com, riandrews@android.com, dan.carpenter@oracle.com, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-api@vger.kernel.org References: <1506518409-16887-1-git-send-email-benjamin.gaignard@linaro.org> <1506518409-16887-3-git-send-email-benjamin.gaignard@linaro.org> <2e15edc2-a17f-3930-7d5b-4b5b7d2e0a4d@redhat.com> <20171003164849.rcdgez6lbpmq5llt@sirena.org.uk> From: Laura Abbott Message-ID: <2417c969-357f-d5d9-153a-2180d09b0dc6@redhat.com> Date: Tue, 3 Oct 2017 14:42:32 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <20171003164849.rcdgez6lbpmq5llt@sirena.org.uk> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/03/2017 09:48 AM, Mark Brown wrote: > On Mon, Oct 02, 2017 at 11:07:48AM -0700, Laura Abbott wrote: > >> Thinking about this a bit more, I'm not 100% sure if this >> will allow the security rules we want. Heap ids are assigned >> dynamically and therefore so will the /dev/ionX designation. >> From my understanding, security rules like selinux need to >> be fully specified at boot time so I'm not sure how you would >> be able to write rules to differentiate between /dev/ionX and >> /dev/ionY without knowing the values at boottime. > > Isn't this something that should be managable via udev rules that ensure > stable names in the same way as for things like disks or ethernet > controllers (even if it just ends up doing something like /dev/ion-gpu > or whatever)? If we're not giving it enough information to assign stable > names where needed we probably need to fix that anyway. > Android doesn't use a standard udev so we'd need something that would work there. My understanding was that android needs everything specified at boot unless that's changed. There would be enough information to assign stable names (e.g. /dev/ion-system) if we used the query ioctl to find out what's actually available. Is just the ioctl useful though? Thanks, Laura