From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gerd Hoffmann Subject: Re: Re: [PATCH] Xen Guest Kexec Date: Mon, 06 Mar 2006 15:15:00 +0100 Message-ID: <440C43E4.1050204@suse.de> References: <08134dbedd3f8cf9e06f9876efe364bb@cl.cam.ac.uk> <44031C17.1030502@suse.de> <497e0e82f56e48142857ac3e0280d691@cl.cam.ac.uk> <44058EED.7060006@suse.de> <4405AB49.9020704@suse.de> <7b7a318fc7204edaf650ffb8e1b11632@cl.cam.ac.uk> <4406B7FB.6030207@suse.de> <4406D83F.3080709@suse.de> <4b02cf0aeca2fb5aa2cfadb0833ec1cc@cl.cam.ac.uk> <44071EFC.6010307@suse.de> <50867f02a9164fec709c96927802dc45@cl.cam.ac.uk> <440800D9.4030803@suse.de> <12462cbf1e480de2105fa4627592b3bf@cl.cam.ac.uk> 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: Ian Pratt , xen-devel@lists.xensource.com, Mark Williamson , Horms List-Id: xen-devel@lists.xenproject.org Hi, Ok, one of the more intresting issues is p2m map and ballooning, I'm not sure yet how to address that best. One problem are the "holes" in guest physical memory created by ballooning. The other one is the time gap between loading and booting the kexec kernel (and the p2m table which may change inbetween). My first attempt to address that issue by avoiding it (features="auto_translated_physmap" ;) resulted in this: kernel BUG at drivers/xen/balloon/balloon.c:216! For now I have a few questions: * Which events can change the p2m map? I think for domU that is only ballooning, right? For dom0 additionally the backend drivers (when mapping foreign pages). Anything else? * Is there some way to rebuild the p2m map from scratch using hypercalls? * Is there some easy way to "compress" the memory, i.e. move all pages to the start of (guest physical) memory? * Are unpriviledged domains allowed to do Dom0 ops for DOM_SELF? getdomaininfo for example? Or hypercall_init? cheers, Gerd -- Gerd 'just married' Hoffmann I'm the hacker formerly known as Gerd Knorr. http://www.suse.de/~kraxel/just-married.jpeg