Re: [PATCH v2] x86/HVM: change the flags cpu context field to uint64_t

["Roger Pau Monné" <roger.pau@citrix.com>]

El 18/01/16 a les 16.24, Andrew Cooper ha escrit:
> On 18/01/16 15:21, Jan Beulich wrote:
>>>>> On 18.01.16 at 16:09, <roger.pau@citrix.com> wrote:
>>> --- a/xen/include/public/arch-x86/hvm/save.h
>>> +++ b/xen/include/public/arch-x86/hvm/save.h
>>> @@ -161,8 +161,8 @@ struct hvm_hw_cpu {
>>>      uint32_t error_code;
>>>  
>>>  #define _XEN_X86_FPU_INITIALISED        0
>>> -#define XEN_X86_FPU_INITIALISED         (1U<<_XEN_X86_FPU_INITIALISED)
>>> -    uint32_t flags;
>>> +#define XEN_X86_FPU_INITIALISED         (1UL<<_XEN_X86_FPU_INITIALISED)
>>> +    uint64_t flags;
>>>  };
>> How is the UL going to make this safe for a 32-bit consumer?
>> Makes me think that, other than just said in reply to v1, it'll
>> indeed be better to have a separate field (with a separate
>> zero-check)... The (undesirable imo) alternative being to use
>> 1L instead.
> 
> I am happy either way.  My R-b stands.

What about using ULL or simply casting to uint64_t?

Roger.