Re: [PATCH v2 0/6] Deprecate support for 32-bit x86 and arm hosts

From: Thomas Huth <thuth@redhat.com>
To: "Philippe Mathieu-Daudé" <philmd@linaro.org>,
	qemu-devel@nongnu.org, "Peter Maydell" <peter.maydell@linaro.org>,
	"Daniel Berrange" <berrange@redhat.com>,
	"Paolo Bonzini" <pbonzini@redhat.com>
Cc: "Markus Armbruster" <armbru@redhat.com>,
	"Alex Bennée" <alex.bennee@linaro.org>,
	qemu-arm@nongnu.org, "Maxim Levitsky" <mlevitsk@redhat.com>,
	libvir-list@redhat.com,
	"Richard Henderson" <richard.henderson@linaro.org>,
	xen-devel@lists.xenproject.org,
	"Reinoud Zandijk" <reinoud@netbsd.org>,
	"Michael Tokarev" <mjt@tls.msk.ru>,
	"John Paul Adrian Glaubitz" <glaubitz@physik.fu-berlin.de>,
	"Helge Deller" <deller@gmx.de>
Subject: Re: [PATCH v2 0/6] Deprecate support for 32-bit x86 and arm hosts
Date: Fri, 3 Mar 2023 10:48:16 +0100	[thread overview]
Message-ID: <6c1f0d05-924e-854e-0175-5e345945e086@redhat.com> (raw)
In-Reply-To: <4bed38c3-ab4f-cd32-05a4-afa090ad8b9a@linaro.org>

On 02/03/2023 23.07, Philippe Mathieu-Daudé wrote:
> On 2/3/23 17:31, 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.com/
>>
>> 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 x86 host support and for system emulation on
>> 32-bit arm hosts anymore, so it should be fine if we drop these host
>> environments soon (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).
> 
> It is not clear from your cover that the deprecation only concern system
> emulation on these hosts, not user emulation.

x86 ==> deprecate both, user and system emulation support on
         32-bit hosts
arm ==> deprecate only system emulation on 32-bit hosts.

I tried to say it with the sentence "there is no real need for 32-bit x86 
host support and for system emulation on 32-bit arm hosts anymore, so it 
should be fine if we drop these host  environments soon" ... not sure why 
it's unclear, but if you have some better sentences, I'm open for suggestions.

> I wonder about tools. Apparently they depend on sysemu now. I was
> building a 'configure --enable-tools --disable-system' but now it
> is empty.

I just did a try in a fresh build directory, and for me it was working: it 
builds qemu-img, qemu-io, qemu-edid etc. just fine.

What was missing in your case?

  Thomas