From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sergiy Kibrik Subject: Re: [RFC][PATCH v1] xen-fbfront: replace deferred io with buffer queue Date: Mon, 19 Jan 2015 18:39:55 +0200 Message-ID: <54BD335B.6080300@globallogic.com> References: <1421668996-23935-1-git-send-email-sergiy.kibrik@globallogic.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1YDFMy-0000R8-GF for xen-devel@lists.xenproject.org; Mon, 19 Jan 2015 16:40:04 +0000 Received: by mail-wg0-f43.google.com with SMTP id k14so32713796wgh.2 for ; Mon, 19 Jan 2015 08:39:59 -0800 (PST) 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: Stefano Stabellini Cc: xen-devel@lists.xenproject.org List-Id: xen-devel@lists.xenproject.org On 1/19/2015 3:25 PM, Stefano Stabellini wrote: >> This doesn't sound like a secure interface: a potentially very >> > significant and unbound memory allocation in dom0 is caused by a >> > parameter configured by the guest. > > Sorry, I realize now that fortunately it is the other way around. > It would be nice to see a correspondent patch for xenfb (the backend). > Who configures num_bufs initially in your system? > AFAIK there's no backend code in xen-4.x tree anymore, I found it in old releases. But I'll find a way to present backend as well. num_bufs should be set by xl tool according to domain config file, but we don't have patch for xl yet (it's done manually via xenstore-write in our setup. Fairly ugly) -- regards, Sergey