Re: [PATCH 1/3] x86-32: Separate 1:1 pagetables from swapper_pg_dir

[Borislav Petkov <bp@amd64.org>]

On Wed, Dec 08, 2010 at 04:34:15AM -0500, Ian Campbell wrote:
> On Wed, 2010-12-08 at 04:15 +0000, Greg KH wrote:
> > On Tue, Dec 07, 2010 at 07:06:31PM -0800, Jeremy Fitzhardinge wrote:
> > > On 12/07/2010 01:05 PM, Greg KH wrote:
> > > > On Thu, Nov 11, 2010 at 04:16:14PM +0100, Joerg Roedel wrote:
> > > >> commit fd89a137924e0710078c3ae855e7cec1c43cb845 upstream
> > > > applied, thanks.
> > > 
> > > This will need as well 5b5c1af104ab5adec1be9dcb4c787492d83d8d83 to
> > > prevent Xen regressions.
> >
> > So should I add that to a specific release? The next .36 stable or something else?
> 
> 5b5c1af104ab5 fixed an issue exposed by b40827fa7268. I'm not sure if
> fd89a13792 also exposes a similar issue, but I think it does not:
> 
> It looks to me like fd89a13792 only reads from swapper_pg_dir and writes
> to trampoline_pg_dir which is unpinned (and unused) under Xen and hence
> there is no problem and 5b5c1af104ab5 is not needed.

I tend to agree with Ian's assessment here.

Let me put it this way: have you guys seen any Xen-related regressions
with fd89a13792? I mean, this patch went in after 2.6.36-rc1 and if
it were breaking Xen, we (or maybe you :)) would've caught it by now,
right?

> b40827fa7268 is in 2.6.37-rc and doesn't seem to be targeted for a
> stable backport AFAICT.

Nope, since it's not fixing a bug or fits any other of the stable rules.

-- 
Regards/Gruss,
Boris.

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