Re: [PATCH] KVM: Add CPUID support for VIA CPU

[Avi Kivity <avi@redhat.com>]

On 04/13/2011 06:26 AM, BrillyWu@viatech.com.cn wrote:
> The CPUIDs for Centaur are added, and then  the features of PadLock
> hardware
> engine on VIA CPU, such as "ace", "ace_en" and so on, can be passed into
> the
> kvm guest.
>

Nice to see this.  Please post a link to the documentation describing 
these features.

>
> +	/* cpuid 0xC0000001.edx */
> +	const u32 kvm_supported_word5_x86_features =
> +		F(XSTORE) | F(XSTORE_EN) | F(XCRYPT) | F(XCRYPT_EN) |
> +		F(ACE2) | F(ACE2_EN) | F(PHE) | F(PHE_EN) |
> +		F(PMM) | F(PMM_EN);
> +

Are all of these features save wrt save/restore? (do they all act on 
state in standard registers?)  Do they need any control register bits to 
be active or MSRs to configure?

> @@ -2484,6 +2504,17 @@ static int kvm_dev_ioctl_get_supported_c
>
>   	r = -E2BIG;
>   	if (nent>= cpuid->nent)
> +		goto out_free;
> +
> +	/* Add support for Centaur's CPUID instruction. */
> +	do_cpuid_ent(&cpuid_entries[nent], 0xC0000000, 0,&nent,
> cpuid->nent);

nent overflow check missing here.  Also, should probably skip if not a Via.

> +	limit = cpuid_entries[nent - 1].eax;
> +	for (func = 0xC0000001; func<= limit&&  nent<  cpuid->nent;
> ++func)
> +		do_cpuid_ent(&cpuid_entries[nent], func, 0,
> +			&nent, cpuid->nent);
> +
> +	r = -E2BIG;
> +	if (nent>= cpuid->nent)
>   		goto out_free;
>
>   	do_cpuid_ent(&cpuid_entries[nent], KVM_CPUID_SIGNATURE, 0,
> &nent,

-- 
error compiling committee.c: too many arguments to function