From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH v4 13/17] libxc: arm: allow passing a device tree blob to the guest Date: Wed, 13 Nov 2013 13:42:40 +0000 Message-ID: <528381D0.8080708@linaro.org> References: <1384277936.10204.111.camel@kazak.uk.xensource.com> <1384277960-14426-13-git-send-email-ian.campbell@citrix.com> <1384338086.5406.33.camel@kazak.uk.xensource.com> <1384344971.5406.92.camel@kazak.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1384344971.5406.92.camel@kazak.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell , Stefano Stabellini Cc: Ian Jackson , tim@xen.org, xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On 11/13/2013 12:16 PM, Ian Campbell wrote: > On Wed, 2013-11-13 at 12:01 +0000, Stefano Stabellini wrote: > >>> and in any case this >>> is user space (and common code) so I don't know how we can do so. >> >> Linux offers an __ARM_NR_cacheflush syscall, it is implemented as a >> dcache flush on v7. >> >> >>> IIRC Julien was working on a generic solution for this issue. >> >> What is the generic solution? > > Not sure, could be __ARM_NR_cacheflush or maybe when adding foreign > mappings to a p2m we should make them uncached depending on the target > VCPUs state (in particular when the domain is under construction, I'm > less concerned with domains which turn off caching at runtime). Or maybe > he had some other idea. I plan to implement the solution with __ARM_NR_cacheflush. It's the best approach for now. It's also implemented on v8 with __ARM_NR_compat_cacheflush. -- Julien Grall