From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: Re: APIC rework Date: Mon, 16 Nov 2009 10:37:52 -0800 Message-ID: <4B019C00.2070404@goop.org> References: <4AFDF254.7070407@goop.org> <706158FABBBA044BAD4FE898A02E4BC201CD3201A3@pdsmsx503.ccr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <706158FABBBA044BAD4FE898A02E4BC201CD3201A3@pdsmsx503.ccr.corp.intel.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: "Zhang, Xiantao" Cc: Xen-devel , "Han, Weidong" , Keir Fraser , Konrad Rzeszutek Wilk List-Id: xen-devel@lists.xenproject.org On 11/16/09 02:38, Zhang, Xiantao wrote: > Hi, Keir/Jeremy > After you picking the two patches into upstream, we found it may break old dom0 when assigned a level-triggered devices to a HVM domain. The casue is that, old dom0 can't provide trigger mode and polarity when they do map_domain_pirq. In attached patches, they introduce a bit to indicate whether old dom0 or not. > > xen-introduce-a-bit-to-identify-dom0-type.patch: for hypervisor. > 0001-x86-Introduce-a-bit-MAP_COMPAT-mode-for-MAP_PIRQ_TY.patch: for pv ops dom0. > Is there any way for the dom0 kernel to tell whether the hypervisor is implementing the new ABI, so it can choose how to set up interrupts. MAP_COMPAT_BIT doesn't seem like a very good name, because it implies that setting it reverts to "compatible" behaviour. I assume that leaving it clear enables the historical behaviour and setting it enables the new one (since old kernels won't be setting it). J > Xiantao > > > Keir Fraser wrote: > >> On 13/11/2009 23:57, "Jeremy Fitzhardinge" wrote: >> >> >>>> Sure, I'll check it in. >>>> >>>> >>> How would you feel about backporting this into a stable release? If >>> we start using this interrupt setup mechanism it will be a >>> red-letter day for dom0/xen compatibility. >>> >> There probably won't be another stable release until 4.0 now. There >> will be a 3.4.3 about the same time though. >> >> -- Keir >> >