From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yann E. MORIN Date: Sun, 14 Jul 2019 11:02:56 +0200 Subject: [Buildroot] [PATCH] fs/cpio: make cpio rootfs reproducible In-Reply-To: References: <20190712172320.23108-1-itsatharva@gmail.com> Message-ID: <20190714090256.GJ2680@scaer> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Arnout, Atharva, All, On 2019-07-14 00:34 +0200, Arnout Vandecappelle spake thusly: > On 12/07/2019 19:23, Atharva Lele wrote: > > Pass the recommended argument in the CPIO manual to make cpio archives > > reproducible. [--SNIP--] > > +ifeq ($(BR2_REPRODUCIBLE), y) > > +CPIO_OPTS = --reproducible > > Unfortunately, this option was only introduced in cpio 2.12 (2015). Older > distros, including Debian oldstable and Ubuntu 2016.04, both of which are still > being maintained, have an earlier cpio version (2.11) so don't have this option. > > Therefore, I think we have to check for a suitable system cpio and build > host-cpio if it is not suitable. Or maybe, for reproducible, always build > host-cpio? If we are reproducible, then always build our cpio version. We currently do not have a host-cpio package, but it is relatively trivial to add (patch pending). Yet, I tried and it adds about 25s to the build, somewhat comparable to the overhead for host-tar... If someone gets sufficiently annoyed by the overhead, they'll provide a patch to switch to checking for a suitable cpio. But in any case, I think that people who do care about reproducibility, do care more about it than they do about time. Regards, Yann E. MORIN. -- .-----------------.--------------------.------------------.--------------------. | Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: | | +33 662 376 056 | Software Designer | \ / CAMPAIGN | ___ | | +33 561 099 427 `------------.-------: X AGAINST | \e/ There is no | | http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL | v conspiracy. | '------------------------------^-------^------------------^--------------------'