On 01/17/2018 11:04 AM, Daniel P. Berrange wrote: > On Wed, Jan 17, 2018 at 10:58:21AM -0300, Philippe Mathieu-Daudé wrote: >> On 01/17/2018 07:25 AM, Daniel P. Berrange wrote: >>> On Wed, Jan 17, 2018 at 10:26:36AM +0800, Fam Zheng wrote: >>>> On 01/12/2018 08:49 PM, Philippe Mathieu-Daudé wrote: >>>>> Hi, >>>>> >>>>> This series is to be clearer about which upstream version we are using. >>>>> >>>>> All "FROM distrib:latest" entries have now been removed and replaced by >>>>> explicit "FROM distrib:version" ones. >>>>> >>>>> To keep backward compatibility, a warning is displayed to the user, >>>>> suggesting which correct base image to use. >>>>> >>>>> To be consistent, we remove the deprecated images of the "make docker" >>>>> output. >>>> >>>> Changing image names when a new release comes out is not maintainable for >>>> Fedora and Ubuntu because of the fast pace. Therefore I prefer Paolo's >>>> simple patch. >>> >>> The flipside is that if we release QEMU 2.12 with fedora:27, then for as >>> long >>> as the 2.12 stable branch exists, dockers tests run on that branch will >>> have a >>> consistent target and will be unlikely to break. If we use fedora:latest, >>> then every time a new Fedora comes out there's non-trivial chance that >>> docker >>> builds on all the stable branches will all break due to some new glibc >>> change. >>> Sticking with explicit named versions is a big win in this respect IMHO. >> >> What happened to me twice is checking an older QEMU tag while bisecting >> and being unable to run 'make docker-test' because the older QEMU tag >> use 'latest' which is not the current 'latest' from the Docker library, >> and I had to manually change the tag to the version 'latest' was >> pointing to at the time of the QEMU tag release. >> >> On each stable release we need to freeze the current tag in a new >> Dockerfile, and keep the generic Dockerfile following the 'latest' tag. >> >> Once tagged different that 'latest' the Dockerfile isn't suppose to >> change. So we only maintain the 'latest' version. >> >> Fam/Alex/Daniel do you agree with this approach? > > I don't see a benefit to that as opposed to just updating git master > to the most recent Fedora stable release every 6 months. In fact it is > more work, because it'll require special action by whomever actually > makes the releases. > > Even in git master the use of 'latest' is causing pain. A patch series > of mine passed when i run it in docker because it pulled down fresh > f26 image to my machine, but it failed in patchew because patchew had > latest resolving to a previously cached f25 image. Using explicit > versions all the time will avoid this kind of caching problem.
Oh I misunderstood you, now I get "Sticking with explicit named versions is a big win in this respect IMHO". Yeah, it is indeed clever to avoid to use the 'latest' tag. So we can keep a single Dockerfile per distrib and update tags when necessary. I'll respin following your advice. Thanks, Phil.
