Hi Cyril, On 17/12/2018 15:56, Simon McVittie wrote: > On Thu, 13 Dec 2018 at 17:00:21 +0100, Emilio Pozuelo Monfort wrote: >> On 13/12/2018 16:58, Emilio Pozuelo Monfort wrote: >>> task-pkgs-are-installable-faux depends on task-gnome-desktop, which depends >>> on >>> gnome, which is removed from s390x. I'm not comfortable breaking that, you'd >>> need an ack from Cyril for that. The alternative would be to keep building >>> gnome from src:meta-gnome3 on s390x but removing the deps that are not >>> available, >>> or to apply the proposed mozjs patches from upstream to restore support on >>> s390x >>> if those are enough. >> >> Another option is to restrict the task-gnome-desktop check to !s390x. But >> again >> I'd like an ack from Cyril before doing that in case d-i needs to be updated >> to >> not offer that on s390x. > > For context for those newly Cc'd: > > We have this dependency chain: > > task-gnome-desktop -> gnome-core -> gnome-shell -> gjs -> mozjs{52,60} > > gjs recently switched from mozjs52 to mozjs60, and mozjs60 doesn't work > on s390x (#909536; about 80% of its tests fail, which means I have no > confidence that the resulting binaries would be useful or usable if > we ignored the test failures). As far as I know, the best patches we > have for that are the ones Julien Cristau tested, which might be part > of a solution but are not sufficient on their own to make a reasonable > proportion of the tests pass. (Julien, please correct me if I'm wrong?) > > The GNOME team and the release team both seem to be willing to declare > that the "full-fat" GNOME desktop will not be available on s390x > machines, which are very conspicuously not available in a desktop or > laptop form factor :-) I'm fairly sure that GNOME and Mozilla upstream > have no interest in supporting s390x mainframes either. As a result we > have arranged for all the JavaScript-based GNOME packages (most notably > gnome-shell), and the gnome-core and gnome metapackages, to not be built > on s390x. However, this leaves us with an important task package that > isn't installable on a release architecture, causing migration to fail. > > I suspect gnome-shell may have never worked acceptably on s390x in any > case, since mainframes are not noted for their 3D graphics hardware, > and s390x is not currently whitelisted to build the llvmpipe software > renderer in mesa's debian/rules (I believe the Mesa maintainers are > willing to enable llvmpipe on new architectures after a porter has tested > it and told them it works, so a s390x porter could usefully try that out). > > The options I can see are: > > * Accept that task-gnome-desktop is not going to be installable on s390x. > Change the testing migration scripts to skip installability testing for > that package on s390x, or ignore the fact that it fails. Optionally > change tasksel to make task-gnome-desktop Architecture: any, and give it > some Build-Depends-Arch that are not satisfiable on s390x so that it will > not be built there. > - s390x d-i users will not be able to install a GNOME desktop. Hopefully > the menu item would not appear, and task-desktop would pick up the > second-preference desktop instead, which currently seems to be XFCE? > - Risk: is it possible to ignore uninstallability of task-gnome-desktop > without ignoring uninstallability of other task packages? > > * Require task-gnome-desktop to be installable on s390x, but modify > meta-gnome3 so that on s390x, gnome-core installs something that is not > the full GNOME 3 desktop used on other architectures, for example > the GNOME-2-derived gnome-session-flashback instead of gnome-session and > gnome-shell, and lightdm instead of gdm3. > - s390x users will not get the same GNOME desktop everyone else does. > - Risk: if GNOME Flashback becomes unsupportable in some future release > (it's a GNOME 2 derivative a bit like MATE, although without using > forks of the apps, and most upstream and downstream GNOME maintainers > don't use or maintain it), we're back where we started. > > * Require task-gnome-desktop to be installable on s390x, but modify > meta-gnome3 so that on s390x, gnome-core doesn't install a whole desktop > enviroment at all, just the GNOME applications. > - s390x users will not get a GNOME desktop at all. > - Risk: this is not what the user asked for or expected. > > * Require task-gnome-desktop to be installable on s390x, but modify > either tasksel or meta-gnome3 so that on s390x, task-gnome-desktop > installs some GNOME-derived but non-GNOME desktop environment like MATE. > - s390x users will not get the same desktop environment everyone > else does. > - Risk: this is not what the user asked for or expected. > > I don't think waiting for someone who understands s390x to fix gjs-on-s390x > is an option, although s390x porters are very welcome to prove me wrong!
Any thoughts on the proposed solutions for this task-gnome-desktop installability issue on s390x now that mozjs is not working there? Thanks, Emilio