Re: [PATCH 0/2] Deprecate support for 32-bit x86 and arm hosts

On Tue, Feb 28, 2023 at 08:39:49AM +0100, Thomas Huth wrote: > On 27/02/2023 19.38, Daniel P. Berrangé wrote: >> On Mon, Feb 27, 2023 at 12:10:48PM +0100, Thomas Huth wrote: >>> We're struggling quite badly with our CI minutes on the shared >>> gitlab runners, so we urgently need to think of ways to cut down >>> our supported build and target environments. qemu-system-i386 and >>> qemu-system-arm are not really required anymore, since nobody uses >>> KVM on the corresponding systems for production anymore, and the >>> -x86_64 and -arch64 variants are a proper superset of those binaries. >>> So it's time to deprecate them and the corresponding 32-bit host >>> environments now. >>> >>> This is a follow-up patch series from the previous discussion here: >>> >>> https://lore.kernel.org/qemu-devel/20230130114428.1297295-1-thuth@redhat.... >>> >>> where people still mentioned that there is still interest in certain >>> support for 32-bit host hardware. But as far as I could see, there is >>> no real need for 32-bit host support for system emulation on x86 and >>> arm anymore, so it should be fine if we drop these host environments >>> now (these are also the two architectures that contribute the most to >>> the long test times in our CI, so we would benefit a lot by dropping >>> those). >> >> Your description here is a little ambiguous about what's being >> proposed. When you say dropping 32-bit host support do you mean >> just for the system emulator binaries, or for QEMU entirely ? > > Just for system emulation. Some people said that user emulation still might > be useful for some 32-bit environments. > >> And when the deprecation period is passed, are you proposing >> to actively prevent 32-bit builds, or merely stopping CI testing >> and leave 32-bit builds still working if people want them ? > > CI is the main pain point, so that's the most important thing. So whether we > throw a warning or a hard error while configuring the build, I don't care > too much. If we're merely wanting to drop CI support, we can do that any time and deprecation is not required/expected. We should only be using deprecation where we're explicitly intending that the code will cease to work.