Re: [PATCH] pvh: set cr4 flags for APs

From: Konrad Rzeszutek Wilk
Date: Mon Feb 03 2014 - 15:44:02 EST


On Mon, Feb 03, 2014 at 02:52:40PM -0500, Konrad Rzeszutek Wilk wrote:
> On Mon, Feb 03, 2014 at 11:30:01AM -0800, Mukesh Rathor wrote:
> > On Mon, 3 Feb 2014 06:49:14 -0500
> > Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx> wrote:
> >
> > > On Wed, Jan 29, 2014 at 04:15:18PM -0800, Mukesh Rathor wrote:
> > > > We need to set cr4 flags for APs that are already set for BSP.
> > >
> > > The title is missing the 'xen' part.
> >
> > The patch is for linux, not xen.
>
> Right. And hence you need to prefix the title with 'xen' in it
> otherwise it won't be obvious from the Linux log line for what
> component of the Linux tree it is.
>
> >
> > > I rewrote it a bit and I think this should go in 3.14.
> > >
> > > David, Boris: It is not the full fix as there are other parts to
> > > make an PVH guest use 2MB or 1GB pages- but this fixes an obvious
> > > bug.
> > >
> > >
> > >
> > > From 797ea6812ff0a90cce966a4ff6bad57cbadc43b5 Mon Sep 17 00:00:00 2001
> > > From: Mukesh Rathor <mukesh.rathor@xxxxxxxxxx>
> > > Date: Wed, 29 Jan 2014 16:15:18 -0800
> > > Subject: [PATCH] xen/pvh: set CR4 flags for APs
> > >
> > > The Xen ABI sets said flags for the BSP, but it does
> >
> > NO it does not. I said it few times, it's set by probe_page_size_mask
> > (which is in linux) for the BSP. The comment below also says it.
>
> Where does it set it for APs? Can we piggyback on that?

And since I am in a hurry to fix an build regression I did the research
myself - but this kind of information needs to be in the commit message.

Here is what I have, please comment as I want to send a git pull to Linux
within the hour.