From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by yocto-www.yoctoproject.org (Postfix, from userid 118) id 6B4D2E00911; Fri, 7 Nov 2014 07:27:46 -0800 (PST) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on yocto-www.yoctoproject.org X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham version=3.3.1 X-Spam-HAM-Report: * -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] Received: from mail.ahsoftware.de (h1446028.stratoserver.net [85.214.92.142]) by yocto-www.yoctoproject.org (Postfix) with ESMTP id A4159E00863 for ; Fri, 7 Nov 2014 07:27:34 -0800 (PST) Received: by mail.ahsoftware.de (Postfix, from userid 65534) id 7316D2C9C207; Fri, 7 Nov 2014 16:27:30 +0100 (CET) Received: from eiche.ahsoftware (p4FC3685E.dip0.t-ipconnect.de [79.195.104.94]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.ahsoftware.de (Postfix) with ESMTPSA id DA4972C9C201 for ; Fri, 7 Nov 2014 16:27:29 +0100 (CET) Received: by eiche.ahsoftware (Postfix, from userid 65534) id 41DC28E4B8; Fri, 7 Nov 2014 16:27:26 +0100 (CET) Received: from krabat.ahsoftware (unknown [IPv6:feee::5246:5dff:fe8b:95f8]) by eiche.ahsoftware (Postfix) with ESMTP id BECA97F846; Fri, 7 Nov 2014 15:26:08 +0000 (UTC) Message-ID: <545CE48E.7050600@ahsoftware.de> Date: Fri, 07 Nov 2014 16:26:06 +0100 From: Alexander Holler User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.7.0 MIME-Version: 1.0 To: Otavio Salvador References: <1415353415-3805-1-git-send-email-holler@ahsoftware.de> <1415353415-3805-2-git-send-email-holler@ahsoftware.de> <545CD9F0.50207@ahsoftware.de> In-Reply-To: Cc: "meta-freescale@yoctoproject.org" , Jon Nettleton Subject: Re: [PATCH 1/1] arm: imx: fsl_otp: make fuses (OTP memory) read-only X-BeenThere: meta-freescale@yoctoproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Usage and development list for the meta-fsl-* layers List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 07 Nov 2014 15:27:46 -0000 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Am 07.11.2014 16:06, schrieb Otavio Salvador: > On Fri, Nov 7, 2014 at 12:40 PM, Alexander Holler wrote: >> Am 07.11.2014 um 12:34 schrieb Otavio Salvador: >>> >>> On Fri, Nov 7, 2014 at 7:43 AM, Alexander Holler >>> wrote: >>>> >>>> Nothing in userspace should be able to kill the HW. >>>> Not even just as root and for sure not that easy. >>>> >>>> For obvious reason, I haven't tested this patch thoroughly. >>>> >>>> Reported-by: Jon Nettleton >>>> Signed-off-by: Alexander Holler >>> >>> >>> I have a mix of feelings about the patch. >>> >>> Long story, short: >>> >>> - We ought to have a FSL_OTP_WRITE_SUPPORT config option >>> >>> The writing support is specially useful for manufacturing images where >>> we can use Linux to do the initial programing, consult a database to >>> find out inventory information (MAC address for example) and do proper >>> programing on the OTP fuses. However I also believe we shouldn't have >>> this available on regular kernel images as it is easy to get a >>> 'expensive paper weight'. >>> >>> So would you be keen to rework the patch and include a write support >>> config option? >> >> >> No. >> >> Sorry but I really think such dangerous stuff never should make it's way >> into any kernel which doesn't have big red and yellow signs attached to >> it. And unfortunately that isn't possible. >> >> And even if it would be possible to mark kernels as dangerous, I think >> that functionality should only be part of a bootloader where it isn't >> reachable by normal userspace. > > Ok so I am here Nacking your patch. Feel free to so. Seems to be part of your responsibility. Alexander Holler