From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id CF08D6B006A for ; Mon, 18 Jan 2010 03:37:42 -0500 (EST) Message-ID: <4B541D08.9040802@zytor.com> Date: Mon, 18 Jan 2010 00:34:16 -0800 From: "H. Peter Anvin" MIME-Version: 1.0 Subject: Re: [PATCH v3 04/12] Add "handle page fault" PV helper. References: <1262700774-1808-1-git-send-email-gleb@redhat.com> <1262700774-1808-5-git-send-email-gleb@redhat.com> <1263490267.4244.340.camel@laptop> <20100117144411.GI31692@redhat.com> In-Reply-To: <20100117144411.GI31692@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Gleb Natapov Cc: Peter Zijlstra , kvm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, avi@redhat.com, mingo@elte.hu, tglx@linutronix.de, riel@redhat.com, cl@linux-foundation.org List-ID: On 01/17/2010 06:44 AM, Gleb Natapov wrote: > On Thu, Jan 14, 2010 at 06:31:07PM +0100, Peter Zijlstra wrote: >> On Tue, 2010-01-05 at 16:12 +0200, Gleb Natapov wrote: >>> Allow paravirtualized guest to do special handling for some page faults. >>> >>> The patch adds one 'if' to do_page_fault() function. The call is patched >>> out when running on physical HW. I ran kernbech on the kernel with and >>> without that additional 'if' and result were rawly the same: >> >> So why not program a different handler address for the #PF/#GP faults >> and avoid the if all together? > I would gladly use fault vector reserved by x86 architecture, but I am > not sure Intel will be happy about it. > That's what it's there for... see Peter Z.'s response. -hpa -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org