Re: [RFC Part2 PATCH v3 18/26] KVM: SVM: Add support for SEV LAUNCH_FINISH command

[Borislav Petkov]

On Mon, Jul 24, 2017 at 03:02:55PM -0500, Brijesh Singh wrote:
> The command is used for finializing the SEV guest launch process.
> 
> Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
> ---
>  arch/x86/kvm/svm.c | 23 +++++++++++++++++++++++
>  1 file changed, 23 insertions(+)
> 
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 9b672eb..7a77197 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -6005,6 +6005,25 @@ static int sev_launch_measure(struct kvm *kvm, struct kvm_sev_cmd *argp)
>  	return ret;
>  }
>  
> +static int sev_launch_finish(struct kvm *kvm, struct kvm_sev_cmd *argp)
> +{
> +	struct sev_data_launch_finish *data;

This one is a very good example why you should do this on the stack:
this struct has a single u32 handle; member. The amount of operations to
do kzalloc and kfree for a single u32 are simply not justified.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix ImendÃrffer, Jane Smithard, Graham Norton, HRB 21284 (AG NÃrnberg)
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