From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Jackson Subject: Re: [PATCH V4 3/7] libxl: add pvusb API Date: Tue, 16 Jun 2015 12:12:39 +0100 Message-ID: <21888.1191.40486.530231@mariner.uk.xensource.com> References: <1433906441-3280-1-git-send-email-cyliu@suse.com> <1433906441-3280-4-git-send-email-cyliu@suse.com> <21887.64856.265751.921367@mariner.uk.xensource.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: George Dunlap Cc: Wei Liu , Ian Campbell , Chunyan Liu , "xen-devel@lists.xen.org" , Jim Fehlig , Simon Cao List-Id: xen-devel@lists.xenproject.org George Dunlap writes ("Re: [Xen-devel] [PATCH V4 3/7] libxl: add pvusb API"): > The "busid" we're talking about here will identify a device at a > particular *port* in the USB topology; the busid will take whatever is > plugged into that particular port. So in the example in my other > thread, the Yubikey "busid" is 2-3.1.2; but if I were to unplug the > yubikey and plud my mouse into that port, the mouse would then be at > 2-3.1.2. What you have just said contradicts Juergen's assertion that the busid is not stable across reboots. I think perhaps the difficulty is that the very first number, the usb controller number, may not be stable, because it depends on the order of device discovery. Ian.