Re: [Xen-devel] Re: [PATCH] Two patches fixing regression introduced by 'x86-64, mm: Put early page table high'

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Mon, May 02, 2011 at 12:59:08PM -0700, H. Peter Anvin wrote:
> On 05/02/2011 12:34 PM, Konrad Rzeszutek Wilk wrote:
> > On Mon, May 02, 2011 at 11:33:16AM -0700, H. Peter Anvin wrote:
> >> On 05/02/2011 11:08 AM, Konrad Rzeszutek Wilk wrote:
> >>>>
> >>>> My inclination would be to apply your workaround -- are there any
> >>>> adverse effects to doing that?
> >>>
> >>> There is a bootup slowdown (not noticeable). That is because we call the
> >>> 'memblock_find_range' function on every PTE table creation (only during
> >>> bootup of course). 
> >>>
> >>> Testing wise, on the machines on which the regression occurred, with these two
> >>> patches the regression disappears - so that is a good sign. I am testing
> >>> it on some more today to assure myself I am not missing anything.
> >>>
> >>
> >> OK, sounds like a plan then.  I like it because it doesn't affect the
> >> native kernel.
> > 
> > <laughs> I figured :-)
> > 
> > Moving forward I really want to get rid of this wart.
> > 
> > Not sure if it is possible, but I was thinking it would be nice to get
> > you, Yinghai, Jeremy, Stefano all in one place (phone or web-conference thing)
> > to sketch out some ideas and hammer something out.
> > 
> > What days would work best?
> 
> First things first... are you pushing the workaround (you can add my
> Acked-by:) or should I?

I will do it tomorrow and stick your Acked-by on both patches.
> 
> Second... I don't know what physical locations and/or time zones every
> one is in, which is probably the first thing.

EST for me, Jeremy is PST (California), Stefano is in UK, so that is UTC+0, and
no idea where Yinghai is.

But people are on vacation time right now so or until next week, plus
> Third, I will be travelling a lot over the next two weeks, plus we are

.. you are traveling.
> getting close to merge window time, so it might be hard to schedule
> before the merge window.  Are you looking at trying to push something
> for .40?  If so, you probably should have an implementation in mind
> already.  If not, I suggest we aim for after the merge window is over or
> at least quieted down.

.. and I don't have any implementation in mind yet. Was hoping we could
brainstorm something together.

OK, let me bug you guys when the merge window is over.

> 	
> 	-hpa