From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Ostrovsky Subject: Re: [PATCH 2/4] sysctl/libxl: Add interface for returning IO topology data Date: Mon, 08 Dec 2014 09:56:19 -0500 Message-ID: <5485BC13.3030403@oracle.com> References: <1417556050-23364-1-git-send-email-boris.ostrovsky@oracle.com> <1417556050-23364-3-git-send-email-boris.ostrovsky@oracle.com> <5481E39B020000780004D450@mail.emea.novell.com> <5481E564020000780004D47B@mail.emea.novell.com> <5481E6FC.1070905@oracle.com> <54857061020000780004D999@mail.emea.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <54857061020000780004D999@mail.emea.novell.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: Jan Beulich Cc: wei.liu2@citrix.com, ian.campbell@citrix.com, stefano.stabellini@eu.citrix.com, dario.faggioli@citrix.com, ian.jackson@eu.citrix.com, xen-devel@lists.xen.org, ufimtseva@gmail.com, keir@xen.org List-Id: xen-devel@lists.xenproject.org >>> Additionally please add IN and OUT annotations. When I first saw >>> this I assumed they would all be OUT (in which case the long running >>> loop problem mentioned in the reply to one of the other patches >>> wouldn't have been there), matching their CPU counterpart... >> I don't follow this. Are you saying that if ti->max_devs in patch 3/4 is >> an IN (which it is) then we don't have to guard for long-running loops? > If they were all OUT then there wouldn't be a way for the entire > operation to be fooled into going over more devices than there are > in the system. Assuming I add continuations to the loop, too many devices wouldn't be a problem for the hypervisor, would it? If an unreasonable number is provided then eventually copy_from_guest() will fault. -boris