Re: [Qemu-devel] [PATCH v2 for-2.0] target-i386: x86_cpu_get_phys_page_debug(): support 1GB page translation

[Luiz Capitulino <lcapitulino@redhat.com>]

On Wed, 19 Mar 2014 22:58:11 +0100
Andreas Färber <afaerber@suse.de> wrote:

> Am 19.03.2014 22:03, schrieb Luiz Capitulino:
> > Linux guests, when using more than 4GB of RAM, may end up using 1GB pages
> > to store (kernel) data. When this happens, we're unable to debug a running
> > Linux kernel with GDB:
> > 
> > (gdb) p node_data[0]->node_id
> > Cannot access memory at address 0xffff88013fffd3a0
> > (gdb)
> > 
> > GDB returns this error because x86_cpu_get_phys_page_debug() doesn't support
> > translating 1GB pages in IA-32e paging mode and returns an error to GDB.
> > 
> > This commit adds support for 1GB page translation for IA32e paging.
> > 
> > Signed-off-by: Luiz capitulino <lcapitulino@redhat.com>
> 
> Capitulino? :)

Can you or Peter fix it when merging?

> > ---
> > 
> > - I'm proposing this patch for 2.0 because GDB debugging of large Linux
> >   guests is kind of broken
> 
> Agree that it would be nice to fix, but having mainly touched the
> function interface, I am dependent on reviewers here. => rc2 or .1

I think Paolo and/or Jan will review it.

> 
> Regards,
> Andreas
> 
> > 
> > - Changelog v2:
> >   - Move PS bit handling to if (env->hflags & HF_LMA_MASK) block
> >   - Update changelog
> > 
> >  target-i386/helper.c | 9 +++++++++
> >  1 file changed, 9 insertions(+)
>