Re: [PATCH] Extra check in grant table code for mapping of shared frame

[Keir Fraser <keir@xen.org>]

Probably needs Tim to comment on it. Assuming he's any wiser about this code
than the rest of us. ;)

 -- Keir

On 17/09/2012 12:00, "Andres Lagar-Cavilla" <andreslc@gridcentric.ca> wrote:

> pingŠ
> Thanks,
> Andres
> On Sep 13, 2012, at 11:27 AM, Andres Lagar-Cavilla wrote:
> 
>> xen/common/grant_table.c |  9 ++++++---
>> 1 files changed, 6 insertions(+), 3 deletions(-)
>> 
>> 
>> Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>
>> 
>> diff -r 5ce5b53ea68f -r 40b91bed1275 xen/common/grant_table.c
>> --- a/xen/common/grant_table.c
>> +++ b/xen/common/grant_table.c
>> @@ -649,9 +649,12 @@ __gnttab_map_grant_ref(
>>     }
>>     else if ( owner == rd || owner == dom_cow )
>>     {
>> -        if ( gnttab_host_mapping_get_page_type(op, ld, rd) &&
>> -             !get_page_type(pg, PGT_writable_page) )
>> -            goto could_not_pin;
>> +        if ( gnttab_host_mapping_get_page_type(op, ld, rd) )
>> +        {
>> +            if ( (owner == dom_cow) ||
>> +                 !get_page_type(pg, PGT_writable_page) )
>> +                goto could_not_pin;
>> +        }
>> 
>>         nr_gets++;
>>         if ( op->flags & GNTMAP_host_map )
>