Re: [PATCH] x86: drop XSAVEOPT and CLWB build flags

[Alexander Merritt <alexander@edera.dev>]

On 2025-04-03 19:28, Andrew Cooper wrote:
> On 04/04/2025 12:22 am, Alexander M. Merritt wrote:
>> The new toolchain baseline knows both the XSAVEOPT and CLWB 
>> instructions.
> 
> I know that's what I wrote on the ticket, but what I'd forgotten was
> that we only use XSAVEOPT for it's operand.
> 
> Really what we're doing here is knowing CLWB, and also getting rid of
> the XSAVEOPT workaround for somewhat-more-old toolchains.

Will try to be more detailed in the commit message next time, thanks for 
pointing out.

>> +        asm volatile ("clwb %[p]" :: [p] "m" (*(const char 
>> *)(addr)));
> 
> One minor note about whitespace.  We typically have spaces inside the
> outermost brackets on asm statements, as per the clwb() example below.

Makes sense. I had searched for existing examples of this and saw a mix 
with and without spaces.

> Also, given the expression is so simple, I'd just use %0 and drop the
> [p].  It's just line-verbosity here.

Yes, agreed.

> Can fix both on commit if you're happy.
> 
> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>

Yes please do. Thanks for the review!