From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga02.intel.com ([134.134.136.20]) by linuxtogo.org with esmtp (Exim 4.72) (envelope-from ) id 1SSW8K-0001h8-1p for openembedded-core@lists.openembedded.org; Thu, 10 May 2012 18:22:28 +0200 Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga101.jf.intel.com with ESMTP; 10 May 2012 09:12:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,352,1309762800"; d="scan'208";a="139139098" Received: from shamshir.jf.intel.com (HELO [10.24.5.145]) ([10.24.5.145]) by orsmga001.jf.intel.com with ESMTP; 10 May 2012 09:12:33 -0700 Message-ID: <4FABE8F1.1060909@linux.intel.com> Date: Thu, 10 May 2012 09:12:33 -0700 From: Joshua Lock User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 MIME-Version: 1.0 To: openembedded-core@lists.openembedded.org References: <4FAB145D.4080001@linux.intel.com> <4FAB28B5.106@linux.intel.com> <4FAB31B6.1090307@linux.intel.com> <4FAB32A2.1020508@linux.intel.com> In-Reply-To: Subject: Re: [RFC PATCH 0/3] Shared state for all ! X-BeenThere: openembedded-core@lists.openembedded.org X-Mailman-Version: 2.1.11 Precedence: list Reply-To: Patches and discussions about the oe-core layer List-Id: Patches and discussions about the oe-core layer List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 10 May 2012 16:22:28 -0000 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit On 09/05/12 22:16, Khem Raj wrote: > On Wed, May 9, 2012 at 8:14 PM, Joshua Lock wrote: >> On 09/05/12 20:10, Joshua Lock wrote: >>> >>> On 09/05/12 19:32, Joshua Lock wrote: >>>> >>>> On 09/05/12 19:15, Chris Larson wrote: >>>>> >>>>> On Wed, May 9, 2012 at 6:05 PM, Joshua Lock wrote: >>>>>> >>>>>> >>>>>> >>>>>> On 09/05/12 17:50, Chris Larson wrote: >>>>>>> >>>>>>> >>>>>>> On Wed, May 9, 2012 at 5:22 PM, Joshua Lock >>>>>>> wrote: >>>>>>>> >>>>>>>> >>>>>>>> In Yocto #2041[2] Mark reported an issue with reusing shared state >>>>>>>> as a >>>>>>>> different user on the same machine. >>>>>>>> >>>>>>>> Since the whole purpose of shared state is that it be shared I >>>>>>>> decided to >>>>>>>> dig >>>>>>>> into this issue. I wanted to at least be able to use the shared-state >>>>>>>> cache of >>>>>>>> a different user without error, even if all of the objects aren't >>>>>>>> actually used >>>>>>>> (i.e. native, at least on the Edison branch I did most of the testing >>>>>>>> with). >>>>>>>> >>>>>>>> This is an RFC mainly because it changes the permissions of created >>>>>>>> directories, >>>>>>>> sstate files and siginfo files from what they have traditionally >>>>>>>> been. >>>>>>>> >>>>>>>> There is more of the rhyme an reason in the patch commit headers and >>>>>>>> comments >>>>>>>> but tl;dr bb.mkdirhier directories will be 0777 (rwxrwxrwx) with this >>>>>>>> patch, as >>>>>>>> will all of the contents of sstate-cache (siginfo and tgz) files. >>>>>>>> >>>>>>>> This is actually what one would expect from reading the Python API >>>>>>>> docs >>>>>>>> for >>>>>>>> os.makedirs "The default mode is 0777 (octal)."[1] but not what >>>>>>>> actually >>>>>>>> happens >>>>>>>> on most modern Linux systems thanks to umask. >>>>>>>> >>>>>>>> Please review the following changes for suitability for inclusion. >>>>>>>> If you >>>>>>>> have >>>>>>>> any objections or suggestions for improvement, please respond to the >>>>>>>> patches. If >>>>>>>> you agree with the changes, please provide your Acked-by. >>>>>>> >>>>>>> >>>>>>> >>>>>>> 777 seems questionable to me, personally. Generally collaboration >>>>>>> happens amongst folks within a group, and chmod g+s makes that easier. >>>>>>> I'd expect 775 to be a more sane value, myself. >>>>>> >>>>>> >>>>>> >>>>>> Do you mean for bb.mkdirhier calls, the tgz files, the siginfo files or >>>>>> everything? >>>>>> >>>>>> I went with 777 for mkdirhier as that's the default of os.makedirs >>>>>> before >>>>>> umask is involved. I would likely have picked rw-rw-r-- (664) if I >>>>>> weren't >>>>>> trying to request comments. >>>>> >>>>> >>>>> Gotcha. >>>>> >>>>> I'm concerned about the behavior change and potential implications of >>>>> changing the default behavior of mkdirhier. I'm inclined to say that >>>>> when you don't pass mode, let it use the current behavior of obeying >>>>> the umask. >>>> >>>> >>>> An earlier version of the series did this and I'm happy to add that >>>> behaviour back in. >>>> >>>> If we're not going to do that, and want to change the >>>>> >>>>> default behavior, then I think 777 is the wrong/questionable default. >>>>> Beyond that, 777 is certainly the wrong mode to be using for the >>>>> shared state package in sstate.bbclass. >>>> >>>> >>>> Do you have a strong preference on 664 vs. 775 ? >>> >>> >>> I'm leaning towards 664 (rw-rw-r--) for the files and 775 (rwxrwxr-x) >>> for directories, these are the defaults for file and directory creation >>> on Ubuntu 12.04 and Fedora 16. >> >> >> At which point, the obvious "solution" to the bug report is a sanity check >> whether the user can read and write to the sstate directory. > > may be its already taken care of but I will ask anyway, if shared > state is writable for all > how is contention resolved when someone tries to update the shared > state since he/she rebuilt the package for some reason. I think having > a global shared cache to read from but not update it would be > something interesting where shared state is updated by say an > autobuilder and used by developers in their local builds. SSTATE_MIRRORS does this nicely and since it uses the fetcher code that can be a file:// URI or other. Joshua -- Joshua Lock Yocto Project Intel Open Source Technology Centre