Re: PVH update....

[Mukesh Rathor <mukesh.rathor@oracle.com>]

On Thu, 10 Jan 2013 07:34:27 +0000
Keir Fraser <keir.xen@gmail.com> wrote:

> On 10/01/2013 02:20, "Mukesh Rathor" <mukesh.rathor@oracle.com> wrote:
> 
> This one's not rocket science, Mukesh. The hypervisor stack is 8kB,
> and construct_dom0() is trying to allocate a stack frame bigger than
> 8kB. Debug builds enforce the 8kB limit with guard pages. You will
> actually be crashing on the first stack writing instruction after the
> subq, but double fault is imprecise (in fact reported cs:eip is
> undefined for a double fault).

Thanks Keir. Of course that was my first thought, and I tried confirming
it with debug code in PF handler. When I noticed PF was not happening,
I started to think it must be something else combined with the fact
that the subq man page doesnt' say anything about RSP special case,
and it's just decrementing it, and not accessing it. Anyways,  the
whole x86 is a rocket to me :)... 

> You're allocating a ridiculously big local variable on
> construct_dom0's stack. So just don't do that.

Yup, I accidentally was allocating a large char array on stack. Fixed.

Thanks,
Mukesh