From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759075AbZEEXRu (ORCPT ); Tue, 5 May 2009 19:17:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752969AbZEEXRj (ORCPT ); Tue, 5 May 2009 19:17:39 -0400 Received: from sous-sol.org ([216.99.217.87]:55464 "EHLO sequoia.sous-sol.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752021AbZEEXRj (ORCPT ); Tue, 5 May 2009 19:17:39 -0400 Date: Tue, 5 May 2009 16:17:18 -0700 From: Chris Wright To: Gregory Haskins Cc: Avi Kivity , Gregory Haskins , linux-kernel@vger.kernel.org, kvm@vger.kernel.org Subject: Re: [RFC PATCH 0/3] generic hypercall support Message-ID: <20090505231718.GT3036@sequoia.sous-sol.org> References: <20090505132005.19891.78436.stgit@dev.haskins.net> <4A0040C0.1080102@redhat.com> <4A0041BA.6060106@novell.com> <4A004676.4050604@redhat.com> <4A0049CD.3080003@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4A0049CD.3080003@gmail.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Gregory Haskins (gregory.haskins@gmail.com) wrote: > So you would never have someone making a generic > hypercall(KVM_HC_MMU_OP). I agree. Which is why I think the interface proposal you've made is wrong. There's already hypercall interfaces w/ specific ABI and semantic meaning (which are typically called directly/indirectly from an existing pv op hook). But a free-form hypercall(unsigned long nr, unsigned long *args, size_t count) means hypercall number and arg list must be the same in order for code to call hypercall() in a hypervisor agnostic way. The pv_ops level need to have semantic meaning, not a free form hypercall multiplexor. thanks, -chris