From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sun, 3 Feb 2008 03:23:56 +0100 From: Andrea Arcangeli Subject: Re: [patch 2/4] mmu_notifier: Callbacks to invalidate address ranges Message-ID: <20080203022356.GD7185@v2.random> References: <20080201050439.009441434@sgi.com> <20080201050623.344041545@sgi.com> <20080201220952.GA3875@sgi.com> <20080201233528.GE12099@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080201233528.GE12099@sgi.com> Sender: owner-linux-mm@kvack.org Return-Path: To: Robin Holt Cc: Christoph Lameter , Avi Kivity , Izik Eidus , kvm-devel@lists.sourceforge.net, Peter Zijlstra , steiner@sgi.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, daniel.blueman@quadrics.com List-ID: On Fri, Feb 01, 2008 at 05:35:28PM -0600, Robin Holt wrote: > No, we need a callout when we are becoming more restrictive, but not > when becoming more permissive. I would have to guess that is the case > for any of these callouts. It is for both GRU and XPMEM. I would > expect the same is true for KVM, but would like a ruling from Andrea on > that. I still hope I don't need to take any lock in _range_start and that losing coherency (w/o risking global memory corruption but only risking temporary userland data corruption thanks to the page pin) is ok for KVM. If I would have to take a lock in _range_start like XPMEM is forced to do (GRU is by far not forced to it, if it would switch to my #v5) then it would be a problem. -- 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