From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: frame buffer shared by domains on arch arm linux Date: Fri, 23 Jan 2015 13:16:19 +0000 Message-ID: <1422018979.19859.75.camel@citrix.com> References: <54BF64F1.1090300@gmail.com> <54C05E05.1020200@gmail.com> <54C210E3.50100@gmail.com> <1422005091.19859.3.camel@citrix.com> <54C21C86.5010006@gmail.com> <1422007918.19859.19.camel@citrix.com> <54C22128.9040102@gmail.com> <1422009254.19859.32.camel@citrix.com> <54C2270D.2070902@gmail.com> <1422010615.19859.41.camel@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Mao Mingya Cc: "xen-devel@lists.xen.org." , Stefano Stabellini List-Id: xen-devel@lists.xenproject.org On Fri, 2015-01-23 at 21:13 +0800, Mao Mingya wrote: > On a second though, What mode is the serial port working now on ARM > arch? it is able to be shared by Dom0 and guest Dom A given piece of hardware can only be accessed by one entity at a time. Typically one serial port is given to Xen itself. Dom0 then has access to the hvc (hypervisor console), which Xen routes out of its own console (i.e. out of the serial port given to Xen). Dom0 also has access to any additional serial ports in the system. DomU only gets the virtual hvc console, unless you use device pass through (again, coming in 4.6) to give it access to a real one (thereby denying it to dom0. Ian.