Re: [GIT PULL] x86/mm changes for v3.9-rc1

[Konrad Rzeszutek Wilk <konrad@kernel.org>]

> >> how about if we call load_cr3 early several times?
> >> assume you should make xen_write_cr3 more robust,
> >> like bailing out early when cr3 writing same value.
> >
> > I would welcome such patch - but at this point I just want a
> > patch for Linus so that I am not blocking him - and this
> > one works.
> 
> come on, you produce
> 
>   #ifdef CONFIG_X86_32
>          .write_cr3 = xen_write_cr3_init,
>   #else
>          .write_cr3 = xen_write_cr3_init,
>   #endif
> 
> for the fix, Linus should just apply attached patch instead.

I misunderstood you. I thought you were talking about
"how about if we call .. cr3 writing same value" - and that part
I hadn't thought completly through so I did not want to delay
Linus.

Naturally the fixes you pointed out should be in the patch - and
hpa graciously did the fixes and sent to Linus. Thank you Peter!
> 
> >>
> >> Also you should check condition about calling xen_get_user_pgd().
> >
> > Could you elaborate please?
> 
> only call xen_get_user_pgd() when it should be called.

I should have been more explicit. When I was saying "elaborate" I was
soliciting for advice on the 'check condition' and how to make it robust.
> 
> Yinghai