From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [Draft F] Xen on ARM vITS Handling Date: Fri, 12 Jun 2015 14:16:50 +0100 Message-ID: <1434115010.30003.209.camel@citrix.com> References: <1434015607.30003.137.camel@citrix.com> <1434099156.30003.196.camel@citrix.com> <557ADA1C.8050700@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <557ADA1C.8050700@citrix.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: Julien Grall Cc: manish.jaggi@caviumnetworks.com, Julien Grall , Stefano Stabellini , Vijay Kilari , xen-devel List-Id: xen-devel@lists.xenproject.org On Fri, 2015-06-12 at 09:09 -0400, Julien Grall wrote: > Hi Ian, > > On 12/06/2015 04:52, Ian Campbell wrote: > > On Fri, 2015-06-12 at 14:07 +0530, Vijay Kilari wrote: > > So pLPIs must be routed at device assignment time because in the vLPI > > configuration table trap there is no mapping back to a single pLPI. > > I just remembered the exact reason that made use to differ SPI enabling. I can't parse this sentence, differ how? > When the device is assigned, the domain VCPUs are still down (even VCPU0). > > If we receive an interrupt before the VCPU0 is unpaused, the interrupt > will be lost. Same if the interrupt is not yet configured (i.e before > the vITS setup correctly the table) with your proposal. Is this any different to booting with the ITT not setup? (SPIs are a slightly different case because they don't need h/w routing) > This could happen when the device is not quiescent. We had this issue on > the vexpress at boot time when the network card was trying to send an > interrupt before DOM0 is setup. I don't fully understand the issue you are trying to describe, but do you want to propose a change to the spec? Ian.