Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758365Ab3GaJj0 (ORCPT ); Wed, 31 Jul 2013 05:39:26 -0400 Received: from mail-bk0-f51.google.com ([209.85.214.51]:41046 "EHLO mail-bk0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751316Ab3GaJjY (ORCPT ); Wed, 31 Jul 2013 05:39:24 -0400 MIME-Version: 1.0 In-Reply-To: <87zjte9iah.fsf@rustcorp.com.au> References: <51E97779.3020103@zytor.com> <87zjte9iah.fsf@rustcorp.com.au> Date: Wed, 31 Jul 2013 12:39:23 +0300 Message-ID: Subject: Re: [QUERY] lguest64 From: Mike Rapoport To: Rusty Russell Cc: "H. Peter Anvin" , Ramkumar Ramachandra , LKML Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1799 Lines: 50 On Tue, Jul 23, 2013 at 4:28 AM, Rusty Russell wrote: > "H. Peter Anvin" writes: >> On 07/19/2013 02:06 AM, Ramkumar Ramachandra wrote: >>> Hi, >>> >>> I tried building lguest to play with it, but was disappointed to find >>> this in the Kconfig: >>> >>> depends on X86_32 >>> >>> Why is this [1]? What is so hard about supporting 64-bit machines? I >>> found a five-year old tree that claims to do lguest64 [2], but didn't >>> investigate further. >>> Sorry for jumping late, but, coincidentally, I was thinking about extending lguest for 64-bits and while googling about the subj, I've crossed this thread... >> Please don't have us deal with another lguest unless there is a use case >> for it. We want to reduce pvops and pvops users, not increase them... >> >> -hpa The use case I had in mind is to use lguest as a nested hypervisor in public clouds. As of today, major public clouds do not support nested virtualization and it's not clear at all if they will expose this ability in their deployments. Addition of 64-bit support for lguest won't require changes to pvops and, as far as I can tell, won't change the number of pvops users... > Yes, the subset of x86-64 machines for which there isn't hardware > virtualization support is pretty uninteresting. There are plenty virtual machines in EC2, Rackspace, HP and other clouds that do not have hardware virtualization. I believe that running a hypervisor on them may be pretty interesting. > Cheers, > Rusty. -- Sincerely yours, Mike. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/