From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Nadav Har'El" Subject: Re: [PATCH 9/24] Implement VMCLEAR Date: Thu, 5 Aug 2010 15:10:27 +0300 Message-ID: <20100805121027.GE16722@fermat.math.technion.ac.il> References: <1276431753-nyh@il.ibm.com> <201006131227.o5DCRAB0012968@rice.haifa.ibm.com> <20100615134753.GX21797@redhat.com> <4C17852B.5080703@redhat.com> <20100615135405.GY21797@redhat.com> <20100805115025.GC16722@fermat.math.technion.ac.il> <20100805115304.GL10499@redhat.com> <20100805120136.GD16722@fermat.math.technion.ac.il> <4C5AA911.4040405@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Gleb Natapov , kvm@vger.kernel.org To: Avi Kivity Return-path: Received: from mailgw12.technion.ac.il ([132.68.225.12]:11176 "EHLO mailgw12.technion.ac.il" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755878Ab0HEMKs (ORCPT ); Thu, 5 Aug 2010 08:10:48 -0400 Content-Disposition: inline In-Reply-To: <4C5AA911.4040405@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On Thu, Aug 05, 2010, Avi Kivity wrote about "Re: [PATCH 9/24] Implement VMCLEAR": > As far as the processor is concerned, there is no end to physical > memory. The VMCLEAR will write some stuff out, and the chipset will > throw it away. So isn't what you're saying that for accurate VMCLEAR emulation, I should simply ignore this error and have VMCLEAR do nothing in this case? > However, eventually the guest will crash and burn, > better to take it out in a controlled way. Isn't it concievable that some poorly-written hypervisor actually VMCLEARs something beyond available memory, and doesn't crash because it never tries to actually use that memory later? Do you think it's a good idea to kill the guest immediately, in anticipation of a crash that will most likely come later? Thanks, Nadav. -- Nadav Har'El | Thursday, Aug 5 2010, 25 Av 5770 nyh@math.technion.ac.il |----------------------------------------- Phone +972-523-790466, ICQ 13349191 |Tact is the art of making a point without http://nadav.harel.org.il |making an enemy.