Re: [PATCH] KVM: x86: Store multiple cpuid entries for a single function

[Muli Ben-Yehuda <muli@il.ibm.com>]

On Mon, Jan 12, 2009 at 10:49:25AM +0000, Amit Shah wrote:
> CPUID functions 4, 0xb and 0xd behave differently for different values of ECX.
> Store these values if userspace passes them.
> 
> Signed-off-by: Amit Shah <amit.shah@redhat.com>
> ---
>  arch/x86/kvm/x86.c |   18 +++++++++++++++---
>  1 files changed, 15 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 06b44fb..8dc4b29 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -1126,7 +1126,7 @@ static int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
>  				    struct kvm_cpuid *cpuid,
>  				    struct kvm_cpuid_entry __user *entries)
>  {
> -	int r, i;
> +	int r, i, count;
>  	struct kvm_cpuid_entry *cpuid_entries;
>  
>  	r = -E2BIG;
> @@ -1146,8 +1146,20 @@ static int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
>  		vcpu->arch.cpuid_entries[i].ebx = cpuid_entries[i].ebx;
>  		vcpu->arch.cpuid_entries[i].ecx = cpuid_entries[i].ecx;
>  		vcpu->arch.cpuid_entries[i].edx = cpuid_entries[i].edx;
> -		vcpu->arch.cpuid_entries[i].index = 0;
> -		vcpu->arch.cpuid_entries[i].flags = 0;
> +		switch (cpuid_entries[i].function) {
> +		case 4:
> +		case 0xb:
> +		case 0xd:
> +			vcpu->arch.cpuid_entries[i].index = count++;

Isn't this using count uninitialized?

Cheers,
Muli
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