From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932731Ab0JFOyH (ORCPT ); Wed, 6 Oct 2010 10:54:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:9085 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932572Ab0JFOyE (ORCPT ); Wed, 6 Oct 2010 10:54:04 -0400 Date: Wed, 6 Oct 2010 11:20:50 -0300 From: Marcelo Tosatti To: Gleb Natapov Cc: kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, avi@redhat.com, mingo@elte.hu, a.p.zijlstra@chello.nl, tglx@linutronix.de, hpa@zytor.com, riel@redhat.com, cl@linux-foundation.org Subject: Re: [PATCH v6 03/12] Retry fault before vmentry Message-ID: <20101006142050.GA31423@amt.cnet> References: <1286207794-16120-1-git-send-email-gleb@redhat.com> <1286207794-16120-4-git-send-email-gleb@redhat.com> <20101005155409.GB28955@amt.cnet> <20101006110704.GW11145@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20101006110704.GW11145@redhat.com> User-Agent: Mutt/1.5.20 (2009-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 06, 2010 at 01:07:04PM +0200, Gleb Natapov wrote: > > Can't you set a bit in vcpu->requests instead, and handle it in "out:" > > at the end of vcpu_enter_guest? > > > > To have a single entry point for pagefaults, after vmexit handling. > Jumping to "out:" will skip vmexit handling anyway, so we will not reuse > same call site anyway. I don't see yet why the way you propose will have > an advantage. What i meant was to call pagefault handler after vmexit handling. Because the way it is in your patch now, with pre pagefault on entry, one has to make an effort to verify ordering wrt other events on entry processing. With pre pagefault after vmexit, its more natural. Does that make sense?