From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [kvmarm] [PATCH v10 07/14] KVM: ARM: Memory virtualization setup Date: Sun, 19 Aug 2012 16:00:09 +0300 Message-ID: <5030E359.5040201@redhat.com> References: <20120816152637.21484.65421.stgit@ubuntu> <20120816152918.21484.48428.stgit@ubuntu> <10AE40D4-7DF6-466F-B5F7-1352BD37DA62@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Christoffer Dall , Alexander Graf , kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org To: Peter Maydell Return-path: Received: from mx1.redhat.com ([209.132.183.28]:47752 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751538Ab2HSNAr (ORCPT ); Sun, 19 Aug 2012 09:00:47 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On 08/19/2012 12:38 PM, Peter Maydell wrote: > On 19 August 2012 05:34, Christoffer Dall wrote: >> On Thu, Aug 16, 2012 at 2:25 PM, Alexander Graf wrote: >>> A single hva can have multiple gpas mapped, no? At least that's what I gathered >>> from the discussion about my attempt to a function similar to this :). > >> I don't think this is the case for ARM, can you provide an example? We >> use gfn_to_pfn_prot and only allow user memory regions. What you >> suggest would be multiple physical addresses pointing to the same >> memory bank, I don't think that makes any sense on ARM hardware, for >> x86 and PPC I don't know. > > I don't know what an hva is, host virtual address (see Documentation/virtual/kvm/mmu.txt for more TLAs in this area). but yes, ARM boards can have the same > block of RAM aliased into multiple places in the physical address space. > (we don't currently bother to implement the aliases in qemu's vexpress-a15 > though because it's a bunch of mappings of the low 2GB into high > addresses mostly intended to let you test LPAE code without having to > put lots of RAM on the hardware). Even if it weren't common, the API allows it, so we must behave sensibly. -- error compiling committee.c: too many arguments to function