Re: [PATCH] x86/svm: Fold nsvm_{wr,rd}msr() into svm_msr_{read,write}_intercept()

[Jan Beulich <jbeulich@xxxxxxxx>]

On 21.07.2020 19:22, Andrew Cooper wrote:
> ... to simplify the default cases.
> 
> There are multiple errors with the handling of these three MSRs, but they are
> deliberately not addressed this point.
> 
> This removes the dance converting -1/0/1 into X86EMUL_*, allowing for the
> removal of the 'ret' variable.
> 
> While cleaning this up, drop the gdprintk()'s for #GP conditions, and the
> 'result' variable from svm_msr_write_intercept() is it is never modified.
> 
> No functional change.
> 
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>

Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>

However, ...

> @@ -2085,6 +2091,22 @@ static int svm_msr_write_intercept(unsigned int msr, 
> uint64_t msr_content)
>              goto gpf;
>          break;
>  
> +    case MSR_K8_VM_CR:
> +        /* ignore write. handle all bits as read-only. */
> +        break;
> +
> +    case MSR_K8_VM_HSAVE_PA:
> +        if ( (msr_content & ~PAGE_MASK) || msr_content > 0xfd00000000ULL )

... while you're moving this code here, wouldn't it be worthwhile
to at least fix the > to be >= ?

Jan