From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <478C6421.1080802@qumranet.com> Date: Tue, 15 Jan 2008 09:43:29 +0200 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [kvm-devel] mmu notifiers References: <20080109181908.GS6958@v2.random> <47860512.3040607@qumranet.com> <47891A5C.8060907@qumranet.com> <20080113120939.GA3221@sgi.com> <478A03D8.9050308@qumranet.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: kvm-devel@lists.sourceforge.net, linux-mm@kvack.org, Daniel J Blueman , Andrea Arcangeli , Robin Holt List-ID: Christoph Lameter wrote: > On Sun, 13 Jan 2008, Avi Kivity wrote: > > >> I was just explaining how kvm shares memory among guests (which does not >> require mmu notifiers); if you have some other configuration that can benefit >> from mmu notifiers, then, well, great. >> > > I think you have two page tables pointing to the same memory location > right (not to page structs but two ptes)? Without a mmu notifier the pages > in this memory range cannot be evicted because otherwise ptes of the other > instance will point to a page that is now used for a different purpose. > Even with just one guest we can't swap well without mmu notifiers. kvm constructs new page tables for the guest that the Linux vm doesn't know about, so when Linux removes all the ptes, we need a callback to remove the kvm private ptes (and tlb entries). -- error compiling committee.c: too many arguments to function -- 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