Re: [regression] commit d298b03506d3 ("x86/fpu: Restore the masking out of reserved MXCSR bits")

[Ville Syrjälä]

On Thu, Oct 14, 2021 at 04:56:56PM +0200, Borislav Petkov wrote:
> On Thu, Oct 14, 2021 at 05:43:14PM +0300, Ville Syrjälä wrote:
> > Hmm. Actually I just stared at the code a bit more it looks
> > a bit funny. Was it supposed to do this instead?
> > 
> > - fpu->state.fxsave.mxcsr &= ~mxcsr_feature_mask;
> > + fpu->state.fxsave.mxcsr &= mxcsr_feature_mask;
> 
> Whoops, I had it like that in the original patch:
> 
> https://lore.kernel.org/all/163354193576.25758.8132624386883258818.tip-bot2@tip-bot2/
> 
> I blame tglx. :-)
> 
> Does it work if you remove the mask negation "~"?

The machine is currently preoccupied with other things. Should free up
in an hour or two. Once it does I'll give this a spin and report back.

-- 
Ville Syrjälä
Intel