Re: [PATCH] x86-64: espfix for 64-bit mode *PROTOTYPE*

H. Peter Anvin
2014-04-23T01:43:34Z

On 04/22/2014 06:23 PM, Andrew Lutomirski wrote:
>
> What's the to_dmesg thing for?
>

It's for debugging... the espfix page tables generate so many duplicate
entries that trying to output it via a seqfile runs out of memory. I
suspect we need to do something like skip the espfix range or some other
hack.

> It looks sane, although I haven't checked the detailed register manipulation.
>
> Users of big systems may complain when every single CPU lines up for
> that mutex. Maybe no one cares.

Right now the whole smpboot sequence is fully serialized... that needs
to be fixed.

Konrad - I really could use some help figuring out what needs to be done
for this not to break Xen.

-hpa