Re: [PATCH 01/13] KVM: SVM: Free sev_asid_bitmap during init if SEV setup fails

[Tom Lendacky]

On 1/8/21 6:47 PM, Sean Christopherson wrote:
> Free sev_asid_bitmap if the reclaim bitmap allocation fails, othwerise
> it will be leaked as sev_hardware_teardown() frees the bitmaps if and
> only if SEV is fully enabled (which obviously isn't the case if SEV
> setup fails).

The svm_sev_enabled() function is only based on CONFIG_KVM_AMD_SEV and 
max_sev_asid. So sev_hardware_teardown() should still free everything if 
it was allocated since we never change max_sev_asid, no?

Thanks,
Tom

> Fixes: 33af3a7ef9e6 ("KVM: SVM: Reduce WBINVD/DF_FLUSH invocations")
> Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> ---
>   arch/x86/kvm/svm/sev.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
> index c8ffdbc81709..0eeb6e1b803d 100644
> --- a/arch/x86/kvm/svm/sev.c
> +++ b/arch/x86/kvm/svm/sev.c
> @@ -1274,8 +1274,10 @@ void __init sev_hardware_setup(void)
>   		goto out;
>   
>   	sev_reclaim_asid_bitmap = bitmap_zalloc(max_sev_asid, GFP_KERNEL);
> -	if (!sev_reclaim_asid_bitmap)
> +	if (!sev_reclaim_asid_bitmap) {
> +		bitmap_free(sev_asid_bitmap);
>   		goto out;
> +	}
>   
>   	pr_info("SEV supported: %u ASIDs\n", max_sev_asid - min_sev_asid + 1);
>   	sev_supported = true;