Re: [PATCH] x86: static_cpu_has_safe: discard dynamic check after init

From: H. Peter Anvin
Date: Wed Jan 20 2016 - 10:10:00 EST


On 01/20/16 07:01, Borislav Petkov wrote:
> On Tue, Jan 19, 2016 at 08:02:01PM -0800, H. Peter Anvin wrote:
>> ... "i" (1 << (bit & 7)),
>> "m" (((const char *)boot_cpu_data->x86_capability)[bit >> 3]) ...
>
> Nice!
>
> I was going to do:
>
> "i" (1 << (bit & 31)),
> "m" (((boot_cpu_data->x86_capability)[bit >> 5]))
>

But then you're using testl and get long immediates.

(And the parentheses around boot_cpu_data->x86_capability are redundant.)

-hpa