Re: [PATCH v8 20/40] x86/sev: Use SEV-SNP AP creation to start secondary CPUs

[Brijesh Singh]

On 12/10/21 12:50 PM, Dave Hansen wrote:
> On 12/10/21 7:43 AM, Brijesh Singh wrote:
> > +	vmsa->efer		= 0x1000;	/* Must set SVME bit */
> > +	vmsa->cr4		= cr4;
> > +	vmsa->cr0		= 0x60000010;
> > +	vmsa->dr7		= 0x400;
> > +	vmsa->dr6		= 0xffff0ff0;
> > +	vmsa->rflags		= 0x2;
> > +	vmsa->g_pat		= 0x0007040600070406ULL;
> > +	vmsa->xcr0		= 0x1;
> > +	vmsa->mxcsr		= 0x1f80;
> > +	vmsa->x87_ftw		= 0x5555;
> > +	vmsa->x87_fcw		= 0x0040;
>
> This is a big fat pile of magic numbers.  We also have nice macros for a
> non-zero number of these, like:
>
> 	#define MXCSR_DEFAULT 0x1f80
>
> I understand that this probably _works_ as-is, but it doesn't look very
> friendly if someone else needs to go hack on it.

APM documents the default value for the AP following the RESET or INIT, 
I will define macros and use them accordingly.

thx