From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LFkNT-0000W7-G3 for qemu-devel@nongnu.org; Thu, 25 Dec 2008 02:11:27 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LFkNS-0000Vi-Nh for qemu-devel@nongnu.org; Thu, 25 Dec 2008 02:11:26 -0500 Received: from [199.232.76.173] (port=44428 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LFkNS-0000VZ-Iq for qemu-devel@nongnu.org; Thu, 25 Dec 2008 02:11:26 -0500 Received: from mx2.redhat.com ([66.187.237.31]:33955) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1LFkNS-0005gg-26 for qemu-devel@nongnu.org; Thu, 25 Dec 2008 02:11:26 -0500 Message-ID: <4953322C.2060002@redhat.com> Date: Thu, 25 Dec 2008 09:11:40 +0200 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [Qemu-devel] Merging improvements from VirtualBox OSE into qemu? References: <49522F8D.4000203@turnkeylinux.org> <200812241336.01702.paul@codesourcery.com> <20081224231849.GA1238@shareable.org> In-Reply-To: <20081224231849.GA1238@shareable.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: turnkey-discuss@lists.turnkeylinux.org, Liraz Siri Jamie Lokier wrote: > Paul Brook wrote: > >> Any hardware that supports KVM is already 64-bit, and you're almost >> entirely targetting obsolete hardware. >> > > 32-bit hardware is still in use. My laptop is just over 2 years old, > and there were *no* 64-bit Intel laptop CPUs available when I bought > it (or I would have bought one). > > I use 32-bit KVM very often on my laptop, for OS compatibility > testing, Windows development, BSD development, old Linux development > and binary software packaging. > > (I also use QEMU, with and without KQEMU, to run older guest OSes that > KVM does not work for.) > > To say 32-bit KVM-capable hardware is obsolete implies all _relevant_ > laptop users buy new ones every less than 2 years, which sounds > ridiculous to me. > > Well, your laptop won't run 64-bit guests at native speeds. The VirtualBox hack requires 64-bit capable hardware, more than likely. It just allows you to run a 32-bit host OS. If you do have 64-bit capable hardware, then nothing prevents you from running a 64-bit host OS (still capable of running 32-bit apps) or a 64-bit kernel and 32-bit userspace. The VirtualBox trick is mostly relevant to Windows, where 32-bit is still much more popular than 64-bit. -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain.