Re: [Qemu-devel] [PATCH 1.3?] multiboot: fix e801 memory map

[Paolo Bonzini <pbonzini@redhat.com>]

----- Messaggio originale -----
> Da: "Alexander Graf" <agraf@suse.de>
> A: "Paolo Bonzini" <pbonzini@redhat.com>
> Cc: qemu-devel@nongnu.org
> Inviato: Giovedì, 29 novembre 2012 19:51:07
> Oggetto: Re: [PATCH 1.3?] multiboot: fix e801 memory map
> 
> 
> On 29.11.2012, at 18:11, Paolo Bonzini wrote:
> 
> > The e801 memory sizes in the multiboot structures hard-code the available
> > low memory to 640.  However, the value should not include the size
> > of the EBDA.  Fill the value in the option ROM, getting the size of low
> > memory from the BIOS.
> 
> The description mentions that instead of hard coding, you fetch the
> value dynamically via a BIOS call. However, I don't see the code
> that hard codes it changed. Where is that one?

It is in hw/multiboot.c:

    stl_p(bootinfo + MBI_MEM_LOWER,   640);


Regarding the testcase, Xen will touch the EBDA without this patch and
with http://permalink.gmane.org/gmane.comp.emulators.xen.devel/144855.
However, SeaBIOS does not complain.

Paolo