Re: [Xen-devel] Different esps

[Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>]

> On Tue, 2004-01-20 at 18:08, Steven Hand wrote:
> > > On Tue, 2004-01-20 at 15:42, Jacob Gorm Hansen wrote:
> > > > On Tue, 2004-01-20 at 13:25, Steven Hand wrote:
> > > > > > On Tue, 2004-01-20 at 12:11, Jacob Gorm Hansen wrote:
> > > > > 
> > > > > Anyway, can you post -
> > > > > 
> > > > >   a) what it is you're trying to do in detail (I'm guessing it's 
> > > > >      to do with migration but not sure what stage you're at) and 
> 
> 
> Adding the following to my recover() code changed things a bit, probably
> more Xen state I need to restore before I can live happily ever after:
> 
>     HYPERVISOR_set_trap_table(trap_table);
>     HYPERVISOR_set_fast_trap(SYSCALL_VECTOR);

The alternative is to copy this info between the
full_execution_context's of the old and new domains.
 
> Digging in. While I understand that this may mean I now have various
> nice things such as a page fault handler, I am still puzzled how my
> infinite loop could crash like that.

Looks weird. Why not instrument Xenolinux's trap handlers to see which
exception you are occasionally taking. It's not hard -- most go thru
do_trap() in arch/xeno/kernel/traps.c. GPFs and page faults go thru
separate specialised functions.

 -- keir