Re: [PATCH] KVM: SVM: use __GFP_ZERO instead of clear_page()

From: Maxim Levitsky
Date: Thu Sep 17 2020 - 05:52:22 EST


On Wed, 2020-09-16 at 16:36 +0800, lihaiwei.kernel@xxxxxxxxx wrote:
> From: Haiwei Li <lihaiwei@xxxxxxxxxxx>
>
> Use __GFP_ZERO while alloc_page().
>
> Signed-off-by: Haiwei Li <lihaiwei@xxxxxxxxxxx>
> ---
> arch/x86/kvm/svm/avic.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
> index ac830cd50830..f73f84d56452 100644
> --- a/arch/x86/kvm/svm/avic.c
> +++ b/arch/x86/kvm/svm/avic.c
> @@ -153,20 +153,18 @@ int avic_vm_init(struct kvm *kvm)
> return 0;
>
> /* Allocating physical APIC ID table (4KB) */
> - p_page = alloc_page(GFP_KERNEL_ACCOUNT);
> + p_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
> if (!p_page)
> goto free_avic;
>
> kvm_svm->avic_physical_id_table_page = p_page;
> - clear_page(page_address(p_page));
>
> /* Allocating logical APIC ID table (4KB) */
> - l_page = alloc_page(GFP_KERNEL_ACCOUNT);
> + l_page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
> if (!l_page)
> goto free_avic;
>
> kvm_svm->avic_logical_id_table_page = l_page;
> - clear_page(page_address(l_page));
>
> spin_lock_irqsave(&svm_vm_data_hash_lock, flags);
> again:
Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>

Best regards,
Maxim Levitsky