From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52321) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fY8K9-0004Ce-TZ for qemu-devel@nongnu.org; Wed, 27 Jun 2018 07:09:23 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fY8K6-0001zi-Nu for qemu-devel@nongnu.org; Wed, 27 Jun 2018 07:09:21 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:59568 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fY8K6-0001z7-JU for qemu-devel@nongnu.org; Wed, 27 Jun 2018 07:09:18 -0400 Date: Wed, 27 Jun 2018 12:09:12 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20180627110912.GA2424@work-vm> References: <20180625131253.11218-1-kraxel@redhat.com> <20180625131253.11218-2-kraxel@redhat.com> <6ad67e44-b002-1cd7-cfd1-2d98ebde1a7e@redhat.com> <20180627065126.mwzdxshr3njzok7n@sirius.home.kraxel.org> <0df8a05c-43fc-6e85-b13c-d3f5c4691964@redhat.com> <87fu18ach6.fsf_-_@dusky.pond.sub.org> <20180627085217.blrsx5lmu4sau4fd@sirius.home.kraxel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] Drop support for 32bit hosts in qemu? (was: [PULL 1/6] audio/hda: create millisecond timers that handle IO) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: Gerd Hoffmann , Martin Schrodt , Thomas Huth , Markus Armbruster , QEMU Developers , Max Reitz * Peter Maydell (peter.maydell@linaro.org) wrote: > On 27 June 2018 at 09:52, Gerd Hoffmann wrote: > > Hi, > > > >> > Is QEMU still useful on 32-bit hosts? Honest question! > >> > >> I guess it depends on what 32-bit hosts you consider. If you look at only > >> x86 vs. x86_64 then probably x86 is not that important any more but for some > >> embedded systems/SoCs 32bit might still be common and QEMU useful for those > >> (also as host not only emulated). > > I would generally agree with this. For x86 32-bit is probably > droppable, but for non-x86 the situation is much less clear. > > > Well. I've used kvm with an 32bit arm soc (cubietruck). It's very > > slow. And all the arm architecture improvements to support kvm better > > are for aarch64 only. > > Cubietruck (a Cortex-A7) is a pretty slow 32-bit Arm core. > > Ask again in a couple of years :-) How about dropping support for 32 bit hosts that don't have 64bit atomics? That should be a much smaller set. Dave > thanks > -- PMM > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK