Re: [PATCH] x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue

H. Peter Anvin
2015-04-24T21:47:08Z

On 04/24/2015 01:50 PM, Andy Lutomirski wrote:
>>
>> Exactly my feeling. What are you trying to save? About four CPU
>> cycles of checking %ss != __KERNEL_DS on each switch_to?
>> That's not worth bothering about. Your last patch seems to be perfect.
>
> We'll have to do the write to ss almost every time an AMD CPU sleeps
> in a syscall. Maybe that's still not a big deal.
>

Once you're sleeping anyway, I don't think so.

-hpa