From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gerd Hoffmann Subject: Re: Re: changeset 13403 ... Date: Mon, 29 Jan 2007 15:47:41 +0100 Message-ID: <45BE090D.1050209@suse.de> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: Xen devel list List-Id: xen-devel@lists.xenproject.org Keir Fraser wrote: > > > On 29/1/07 13:48, "Keir Fraser" wrote: > >> On 29/1/07 13:40, "Gerd Hoffmann" wrote: >> >>> Just noticed that domU kexec doesn't work any more, changeset 13403 is >>> the culpit. Hmm. No, it isn't easy to work-around ... >>> >>> cheers, >> Two pagetable switches in a single multicall? First switch is to a pagetable >> which maps only the multicall structure. This small intermediate table has >> to be mapped read-only in the original pagetables and in the final >> pagetables, but it will only be a few pages of memory (4 in the worst case). Helps a bit, but doesn't solve the fundamental problem that I can't use the page tables created by the domain-builder as-is. > Oh, it'll need a hypercall transfer page too. And it's a mmuext_op list that > you need, not a multicall. The transfer page and mmuext_op list can be > placed in adjacent pages so that you don't need any more intermediate > pagetable pages. Hmm. hypercall transfer page? The one with the int 82h instructions? Is the mmuext_op list copyed over before running it? If so, the it should not be required to be mapped all the time, right? In that case I could get away with an empty page as page directory? Or maybe even baseptr=NULL? cheers, Gerd -- Gerd Hoffmann