From mboxrd@z Thu Jan 1 00:00:00 1970 From: George Dunlap Subject: Re: [PATCH] xen: fix initialization of wallclock time for PVHVM on migration Date: Tue, 11 Jun 2013 13:01:37 +0100 Message-ID: <51B711A1.5080105@eu.citrix.com> References: <1370947577-5965-1-git-send-email-roger.pau@citrix.com> <51B72D3602000078000DD0FD@nat28.tlf.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <51B72D3602000078000DD0FD@nat28.tlf.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: xen-devel@lists.xen.org, Keir Fraser , Roger Pau Monne List-Id: xen-devel@lists.xenproject.org On 06/11/2013 12:59 PM, Jan Beulich wrote: >>>> On 11.06.13 at 12:46, Roger Pau Monne wrote: >> The initial values of the wallclock time in the shared info page are >> set for PVHVM guests when the hypercall page is initialized, since the >> hypercall page is not reinitialized on resume, the hypervisor >> wallclock time is not properly set on resume. >> >> Fix it by forcing an update of the wallclock values when the shared >> info page is mapped. > > NACK - this is a guest side bug. After migration, a guest _has_ to > re-init the hypercall page, as it may have got migrated between > a VMX and an SVM machine, and the hypercall instructions are > different between them. Does migrating from VMX to SVM actually work? In any case, if Linux does it, then FreeBSD should do it too. (I assume this came up because you're working on the FreeBSD PVHVM port?) -George