Re: [PATCH v7 06/26] x86/fpu/xstate: Create guest fpstate with guest specific config

[Yang, Weijiang]

On 11/28/2023 11:19 PM, Edgecombe, Rick P wrote:
> On Fri, 2023-11-24 at 00:53 -0500, Yang Weijiang wrote:
> > +static struct fpstate *__fpu_alloc_init_guest_fpstate(struct
> > fpu_guest *gfpu)
> >   {
> > +       bool compacted = cpu_feature_enabled(X86_FEATURE_XCOMPACTED);
> > +       unsigned int gfpstate_size, size;
> >          struct fpstate *fpstate;
> > -       unsigned int size;
> >   
> > -       size = fpu_user_cfg.default_size + ALIGN(offsetof(struct
> > fpstate, regs), 64);
> > +       /*
> > +        * fpu_guest_cfg.default_features includes all enabled
> > xfeatures
> > +        * except the user dynamic xfeatures. If the user dynamic
> > xfeatures
> > +        * are enabled, the guest fpstate will be re-allocated to
> > hold all
> > +        * guest enabled xfeatures, so omit user dynamic xfeatures
> > here.
> > +        */
> > +       gfpstate_size =
> > xstate_calculate_size(fpu_guest_cfg.default_features,
> > +                                             compacted);
> Why not fpu_guest_cfg.default_size here?

Nice catch!
I should use fpu_guest_cfg.default_size directly instead of re-calculating it with the same manner. Thanks!
> > +
> > +       size = gfpstate_size + ALIGN(offsetof(struct fpstate, regs),
> > 64);