From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754404AbbJGNrq (ORCPT ); Wed, 7 Oct 2015 09:47:46 -0400 Received: from mail-wi0-f179.google.com ([209.85.212.179]:36181 "EHLO mail-wi0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754286AbbJGNq7 (ORCPT ); Wed, 7 Oct 2015 09:46:59 -0400 Message-ID: <56152250.2000200@linaro.org> Date: Wed, 07 Oct 2015 14:46:56 +0100 From: Srinivas Kandagatla User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Russell King - ARM Linux CC: gregkh@linuxfoundation.org, stefan.wahren@i2se.com, andrew@lunn.ch, s.hauer@pengutronix.de, pantelis.antoniou@konsulko.com, linux-kernel@vger.kernel.org, maitysanchayan@gmail.com, p.zabel@pengutronix.de, maxime.ripard@free-electrons.com, linux-arm-kernel@lists.infradead.org, wxt@rock-chips.com Subject: Re: [PATCH v2 1/3] nvmem: core: make default user binary file root-access only References: <1444215536-10783-1-git-send-email-srinivas.kandagatla@linaro.org> <1444215647-10836-1-git-send-email-srinivas.kandagatla@linaro.org> <20151007113349.GJ21513@n2100.arm.linux.org.uk> In-Reply-To: <20151007113349.GJ21513@n2100.arm.linux.org.uk> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/10/15 12:33, Russell King - ARM Linux wrote: > On Wed, Oct 07, 2015 at 12:00:47PM +0100, Srinivas Kandagatla wrote: >> As required by many providers like at24/at25/mxs-ocotp/qfprom and may be >> other providers would want to allow root-only to read the nvmem content. >> So making the defaults to be root-only access would address the request >> and also provide flexibility to providers to specify there own permissions >> on top of the root-only using the perm flag in nvmem_config. >> Making this dynamic did cut down lot of static binary attributes in the >> code. > > Check what the lifetime of a struct bin_attribute is before you embed it > into any other structure. Sorry, but I think you're going to have to Lifetime of the "static struct bin_attribute bin_attr_template" is static and a memcpy of which is made into nvmem->bin whose lifetime is till the nvmem_release() which happens at device_release(), so there should be no issue in using a copy of bin_attribute. However there are other issues as Greg pointed, so am dropping this series altogether. --srini > read up on the driver model, sysfs, and kernfs implementations to find > out - I don't know the answer to this without doing the same. > > However, this is basic checking that anyone should do when embedding > a structure within another. >