Re: [Xen-devel] Consuming PCI device in PV kernel

[Simon Martin <furryfuttock@xxxxxxxxx>]

Hello Andrew,

>>>>> Looking at the code I can't see where bit 22 is being set!
>>>> Without seeing you code I've no idea about this (even if I could see it,
>>>> I dunno...)
>>> Bit 22 is being set in Xen code.
>> Hopefully someone who knows the x86 PV stuff can chime in then, I looked
>> but can't see what this represents.

> I suspect this would be:

> /* Bit 22 of a 24-bit flag mask. This corresponds to bit 62 of a pte.*/
> #define _PAGE_GNTTAB (1U<<22)

> from include/asm-x86/x86_64/page.h

> So you are attempting to update a pte which already has a granted page
> in it.

That's  weird  as  I have only one domU running, so nothing else could
have claimed the PCI memory area. The PCI has been passed through as I
see the mapping in xenstore.

Should  I be using a different hypercall to gain access to this memory
area?


-- 
Best regards,
 Simon                            mailto:furryfuttock@xxxxxxxxx


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel