Re: [Qemu-devel] [PATCH] target/ppc: only save guest timebase once after stopping

2018-07-27 Thread Mark Cave-Ayland
On 27/07/18 02:10, David Gibson wrote: Right, I agree. Migrating shouldn't advance the time if we've already explicitly stopped. But it's not really clear how to accomplish that :/. This topic is obviously of interest to me because it relates to various discussions in the past relating to m

Re: [Qemu-devel] [PATCH] target/ppc: only save guest timebase once after stopping

2018-07-26 Thread David Gibson
On Thu, Jul 26, 2018 at 09:44:11AM +0200, Laurent Vivier wrote: > On 26/07/2018 07:07, David Gibson wrote: > > On Thu, May 03, 2018 at 11:20:44PM -0500, Michael Roth wrote: > >> In some cases (e.g. spapr) we record guest timebase after qmp_stop() > >> via a runstate hook so we can restore it on qmp

Re: [Qemu-devel] [PATCH] target/ppc: only save guest timebase once after stopping

2018-07-26 Thread David Gibson
On Thu, Jul 26, 2018 at 07:30:34AM -0500, Michael Roth wrote: > Quoting David Gibson (2018-07-26 00:07:46) > > On Thu, May 03, 2018 at 11:20:44PM -0500, Michael Roth wrote: > > > In some cases (e.g. spapr) we record guest timebase after qmp_stop() > > > via a runstate hook so we can restore it on q

Re: [Qemu-devel] [PATCH] target/ppc: only save guest timebase once after stopping

2018-07-26 Thread Michael Roth
Quoting David Gibson (2018-07-26 00:07:46) > On Thu, May 03, 2018 at 11:20:44PM -0500, Michael Roth wrote: > > In some cases (e.g. spapr) we record guest timebase after qmp_stop() > > via a runstate hook so we can restore it on qmp_cont(). If a migration > > occurs in between those events we end up

Re: [Qemu-devel] [PATCH] target/ppc: only save guest timebase once after stopping

2018-07-26 Thread Laurent Vivier
On 26/07/2018 07:07, David Gibson wrote: > On Thu, May 03, 2018 at 11:20:44PM -0500, Michael Roth wrote: >> In some cases (e.g. spapr) we record guest timebase after qmp_stop() >> via a runstate hook so we can restore it on qmp_cont(). If a migration >> occurs in between those events we end up savi

Re: [Qemu-devel] [PATCH] target/ppc: only save guest timebase once after stopping

2018-07-25 Thread David Gibson
On Thu, May 03, 2018 at 11:20:44PM -0500, Michael Roth wrote: > In some cases (e.g. spapr) we record guest timebase after qmp_stop() > via a runstate hook so we can restore it on qmp_cont(). If a migration > occurs in between those events we end up saving it again, this time > based on the current

[Qemu-devel] [PATCH] target/ppc: only save guest timebase once after stopping

2018-05-03 Thread Michael Roth
In some cases (e.g. spapr) we record guest timebase after qmp_stop() via a runstate hook so we can restore it on qmp_cont(). If a migration occurs in between those events we end up saving it again, this time based on the current timebase the guest would be seeing had it been running. This has the e