From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: [PATCH 0/8] in-kernel APIC support "v1" Date: Sun, 13 May 2007 18:45:17 +0300 Message-ID: <4647328D.1080404@qumranet.com> References: <20070509023731.23443.86578.stgit@novell1.haskins.net> <4646FE71.5080009@qumranet.com> <4646E3D1.BA47.005A.0@novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Gregory Haskins Return-path: In-Reply-To: <4646E3D1.BA47.005A.0-Et1tbQHTxzrQT0dZR+AlfA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org Gregory Haskins wrote: >> I think that it should be writable, as the vcpu wants interrupts to be >> pushed into it (a write op) rather than it indicates it wants data to be >> pulled out of it. >> > > Ok, I think we might just be confusing terms. What you describe is essentially what I do, but I don't do it via an explicit fd based write(). The PIC posts an interrupt to the VCPU, which "writes" to the irq.usignal state. This would then trigger an event to any listeners on the fd. > > Sorry, my fault. I kept saying "writable fd" while neglecting to mention that I don't see the need for any actual write. It's more like a "conceptual write". >> It's certainly the right direction. But we don't support Windows x84 >> yet, which would be the primary (only?) beneficiary? >> > > Agreed. x86_64 TPR consumers only (and only MOV-to-CR8 users at that...if 64 bit windows still uses MMIO we're hosed ;) > > Well, cr8 was certainly designed for Windows. Nothing else uses it AFAIK. I'd be greatly surprised if Windows x86 doesn't use it. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/