From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: How console data travel in Xen? Date: Thu, 30 Jun 2005 13:39:22 -0500 Message-ID: <42C43C5A.6040808@us.ibm.com> References: <5d7aca950506300841306bad7a@mail.gmail.com> <42C4190D.7000809@us.ibm.com> <5d7aca9505063010287ec8117a@mail.gmail.com> <42C43716.4020803@us.ibm.com> <5d7aca95050630113550c453b0@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5d7aca95050630113550c453b0@mail.gmail.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: NAHieu , xen-devel List-Id: xen-devel@lists.xenproject.org NAHieu wrote: >Oops, probably you missed my point: I want to know how the data go >from low level (HW) to Xen (hypervisor), then to dom0. > > I was avoiding answering this because I'm sure that someone who's much smarter than me is going to jump in and correct me on this :-) dom0 takes the keyboard interrupts just like it normally would. I believe (and I may be wrong here) that in x86 the IDT is setup such that keyboard interrupts go directly to the dom0 kernel (since it's in ring 1). I would imagine that in x86-64 that those interrupts have to be reflected back down to the guest OS. This is almost pure speculation though so hopefully someone else will jump in and correct me. >I guess it works this way: dom0 has privileged right to access to HW, >so it can take keyboard code directly (I guess it goes thru Xen, but >dont know exactly how?). Then from dom to domU, it works like you >explained. Is that correct? > >Many thanks, Anthony. >Hieu. > > >