Re: [RFC][PATCH] tracing/x86: Save CR2 before tracing irqsoff on error_entry

[Andy Lutomirski]

On Thu, Mar 21, 2019 at 11:19 AM Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> On Thu, Mar 21, 2019 at 11:05 AM Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote:
> >
> > In the long run, I think the right solution is to rewrite even more of
> > this mess in C.  We really ought to be able to put the IRQ flag
> > tracing and the context tracking into C code.
>
> Tangentially about this long run thing - can we start discussing just
> dropping PV mode entirely in the long run? Or even not-so-long run?
>
> What are the pressing advantages of paravirt these days? Because I can
> point to a lot of pressing _disadvantages_, and not all of them are
> about more complex code as shown by this patch...
>

I dunno.  Lots of people at least use to have serious commercial interest in it.

Hey Xen folks, how close are we to being able to say "if you want to
run a new kernel, you need to switch to PVH or similar"?

--Andy