From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Vrabel Subject: Re: [PATCH v4] add support for libvirt-like channels Date: Thu, 7 Aug 2014 15:12:47 +0100 Message-ID: <53E3895F.1030004@citrix.com> References: <1403512141-12283-1-git-send-email-dave.scott@citrix.com> <1406041520-561-1-git-send-email-dave.scott@citrix.com> <53D65C8A.8040905@citrix.com> <98BD7D14-8B1C-4048-9E3F-8D6BED797AFF@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable Return-path: Received: from mail6.bemta14.messagelabs.com ([193.109.254.103]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1XFOR2-0003DS-LC for xen-devel@lists.xenproject.org; Thu, 07 Aug 2014 14:12:52 +0000 In-Reply-To: <98BD7D14-8B1C-4048-9E3F-8D6BED797AFF@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Dave Scott , David Vrabel Cc: "xen-devel@lists.xenproject.org" , Wei Liu , Ian Campbell , Stefano Stabellini , Ian Jackson List-Id: xen-devel@lists.xenproject.org On 07/08/14 14:37, Dave Scott wrote: > = > On 28 Jul 2014, at 15:22, David Vrabel wrote: > = >> On 22/07/14 16:05, David Scott wrote: >>> >>> Note: I've seen a problem with some Linux console frontends which attem= pt >>> to overwrite the read-only key 'type' (=3D xenconsoled|ioemu) in the fr= ontend >>> directory. [ this key is already present, it's not added by these patch= es ] >>> Since 'type' refers to the toolstack's choice of implementation service >>> (which is none of the guest's business) I think the read/only permissio= ns >>> are right. The location of the key is not ideal (it should be in the >>> backend directory IMHO) but this is the case with several other keys lo= cated >>> in the frontend such as 'limit' and 'tty'. I think this is a Linux fron= tend >>> bug which should be fixed there. These patches work with Mirage VMs and >>> with Linux if I workaround the permissions by giving the guest read/wri= te >>> to the 'type' key. = >> >> Which Linux front ends? > = > I just tested a Debian jessie with > = > # uname -a > Linux jessie 3.13-6-686-pae #1 SMP Debian 3.13.5-1 (2014-03-04) i686 GN= U/Linux > = > In my xenstored access log I see: > = > Aug 7 14:28:30 localhost xenstored: D40.6 write device/con= sole/1/ring-ref 8 > Aug 7 14:28:30 localhost xenstored: D40.6 write device/con= sole/1/port 10 > Aug 7 14:28:30 localhost xenstored: D40.6 write device/con= sole/1/type ioemu > = > =97 I think the last line is suspicious. This was introduced by Stefano in 3.4 with 02e19f9c7cac (hvc_xen: implement multiconsole support). Stefano, can you advise on whether it it safe to remove the write of the "type" key or whether we need to make it conditional on it being absent. David