From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yann E. MORIN Date: Sat, 5 May 2018 17:21:20 +0200 Subject: [Buildroot] [PATCH] Makefile: check rootfs overlays with BR2_ROOTFS_MERGED_USR enabled In-Reply-To: <87h8nmuoya.fsf@dell.be.48ers.dk> References: <20180503121958.9462-1-casantos@datacom.ind.br> <20180505100100.GA2481@scaer> <898911315.1288101.1525528062390.JavaMail.zimbra@datacom.ind.br> <20180505144527.GA14524@scaer> <87h8nmuoya.fsf@dell.be.48ers.dk> Message-ID: <20180505152120.GC14524@scaer> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Peter, All, On 2018-05-05 17:01 +0200, Peter Korsgaard spake thusly: > >>>>> "Yann" == Yann E MORIN writes: > >> > So, I am pretty much reluctant to see this patch go in. > > But I'd prefer we keep things simple in Buildroot, and since there is > > already a way to do it, I don't mind that overlays do not provide this > > solution. A post-build script is way more versatile when it comes to > > changing the layout. > > Yes, with a post-build script you have full flexibility, but we have > quite a lot of helper functionality to handle "common" fixups in a > simpler way than though a post-build script, E.G. stripping, removing > .py files, overlays, .. > > This restriction for overlays isn't obvious and wasn't originally there > (before the merged /usr support), so it is arguably a regression (but > for an edge case as this afaik is the first report of it). I still believe that such *modifications* to the layout be actually not supported with overlays. Today, someone wants to be able to overrids /var/log from a symlink to a directory to be able to store remanent data there. But then, that will require a modification in fstab to mount an actual filesystem there. And such a modification would be done by a post-build script (if it comes from an overlay, there is no way this will work as-is between buildroot versions, becasue buildroot may add/remove stuff in there as well). So, a post-build script is really needed anyway... And then, someone will want to change something else, e.g. a file to a symlink or a directory to a symlink or whatever... Also, overlays are not copied under fakeroot (but OK, post-build script neither, but we have fakeroot-scripts). So, if one wants special rights, it's not possible with overlays either... So, really, overlays are not as nice as one may think... As I said, in the long run, they are more a liability than anything else. Regards, Yann E. MORIN. -- .-----------------.--------------------.------------------.--------------------. | Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: | | +33 662 376 056 | Software Designer | \ / CAMPAIGN | ___ | | +33 223 225 172 `------------.-------: X AGAINST | \e/ There is no | | http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL | v conspiracy. | '------------------------------^-------^------------------^--------------------'