Re: [PATCH Part1 RFC v4 09/36] x86/compressed: Add helper for validating pages in the decompression stage

[Brijesh Singh]

On 8/13/21 5:22 AM, Borislav Petkov wrote:
> > +static void __page_state_change(unsigned long paddr, int op)
>
> That op should be:
>
> enum psc_op {
> 	SNP_PAGE_STATE_SHARED,
> 	SNP_PAGE_STATE_PRIVATE,
> };

Noted.

> and have
>
> static void __page_state_change(unsigned long paddr, enum psc_op op)
>
> so that the compiler can check you're at least passing from the correct
> set of defines.
>
> > diff --git a/arch/x86/include/asm/sev-common.h b/arch/x86/include/asm/sev-common.h
> > index ea508835ab33..aee07d1bb138 100644
> > --- a/arch/x86/include/asm/sev-common.h
> > +++ b/arch/x86/include/asm/sev-common.h
> > @@ -45,6 +45,23 @@
> >   		(((unsigned long)reg & GHCB_MSR_CPUID_REG_MASK) << GHCB_MSR_CPUID_REG_POS) | \
> >   		(((unsigned long)fn) << GHCB_MSR_CPUID_FUNC_POS))
> >   
> > +/* SNP Page State Change */
> > +#define GHCB_MSR_PSC_REQ		0x014
> > +#define SNP_PAGE_STATE_PRIVATE		1
> > +#define SNP_PAGE_STATE_SHARED		2
> > +#define GHCB_MSR_PSC_GFN_POS		12
> > +#define GHCB_MSR_PSC_GFN_MASK		GENMASK_ULL(39, 0)
> > +#define GHCB_MSR_PSC_OP_POS		52
> > +#define GHCB_MSR_PSC_OP_MASK		0xf
> > +#define GHCB_MSR_PSC_REQ_GFN(gfn, op)	\
> > +	(((unsigned long)((op) & GHCB_MSR_PSC_OP_MASK) << GHCB_MSR_PSC_OP_POS) | \
> > +	((unsigned long)((gfn) & GHCB_MSR_PSC_GFN_MASK) << GHCB_MSR_PSC_GFN_POS) | \
> > +	GHCB_MSR_PSC_REQ)
> > +
> > +#define GHCB_MSR_PSC_RESP		0x015
> > +#define GHCB_MSR_PSC_ERROR_POS		32
> > +#define GHCB_MSR_PSC_RESP_VAL(val)	((val) >> GHCB_MSR_PSC_ERROR_POS)
> > +
>
> Also get rid of eccessive defines...

I am getting conflicting review comments on function naming, comment 
style, macro etc. While addressing the feedback I try to incorporate all 
those comments, lets see how I do in next rev.

thanks