Re: [Xen-devel] [PATCH v4 10/16] xen/mm: Switch map_pages_to_xen to use MFN typesafe

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 05.03.18 at 15:07, <julien.grall@xxxxxxx> wrote:
> On 02/03/18 15:06, Jan Beulich wrote:
>>>>> On 21.02.18 at 15:02, <julien.grall@xxxxxxx> wrote:
>>> --- a/xen/arch/x86/x86_64/mm.c
>>> +++ b/xen/arch/x86/x86_64/mm.c
>>> @@ -40,6 +40,10 @@ asm(".file \"" __FILE__ "\"");
>>>   #include <asm/mem_sharing.h>
>>>   #include <public/memory.h>
>>>   
>>> +/* Override macros from asm/page.h to make them work with mfn_t */
>>> +#undef page_to_mfn
>>> +#define page_to_mfn(pg) _mfn(__page_to_mfn(pg))
>> 
>> I can't spot where this is needed in this file.
>> 
>>> @@ -234,7 +238,7 @@ void vunmap(const void *va)
>>>   #ifndef _PAGE_NONE
>>>       destroy_xen_mappings(addr, addr + PAGE_SIZE * pages);
>>>   #else /* Avoid tearing down intermediate page tables. */
>>> -    map_pages_to_xen(addr, 0, pages, _PAGE_NONE);
>>> +    map_pages_to_xen(addr, _mfn(0), pages, _PAGE_NONE);
>> 
>> INVALID_MFN?
> 
> I can but then we end up to the same clumsiness as you mention in #8. So 
> what's your preference?

My preference is to skip the increments for INVALID_MFN in patch 8.
Since you don't want to do that, I guess we'll have to live with zero
being used everywhere.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel