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

Dave Hansen
2021-12-10T18:50:23Z

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.