Re: [PATCH V2 6/7] KVM: X86/MMU: Allocate mmu->pae_root for PAE paging on-demand

From: Lai Jiangshan <jiangshanlai@gmail.com>
To: David Matlack <dmatlack@google.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
	"open list:KERNEL VIRTUAL MACHINE FOR MIPS (KVM/mips)" 
	<kvm@vger.kernel.org>, Paolo Bonzini <pbonzini@redhat.com>,
	Sean Christopherson <seanjc@google.com>,
	Lai Jiangshan <jiangshan.ljs@antgroup.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Wanpeng Li <wanpengli@tencent.com>,
	Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	X86 ML <x86@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH V2 6/7] KVM: X86/MMU: Allocate mmu->pae_root for PAE paging on-demand
Date: Thu, 26 May 2022 16:52:59 +0800	[thread overview]
Message-ID: <CAJhGHyAK7zNQ+XKjGJThtQwmhKAVVNa2+=PgOOOaWfgNg0YA-g@mail.gmail.com> (raw)
In-Reply-To: <YoPT6petoQUnF4vB@google.com>

Hello

Thank you for the review.

On Wed, May 18, 2022 at 12:57 AM David Matlack <dmatlack@google.com> wrote:

> >
> > -static int __kvm_mmu_create(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
> > +static void __kvm_mmu_create(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
>
> vcpu is now unused.

Removed in V3.

>
> >  {
> > -     struct page *page;
> >       int i;
> >
> >       mmu->root.hpa = INVALID_PAGE;
> >       mmu->root.pgd = 0;
> >       for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++)
> >               mmu->prev_roots[i] = KVM_MMU_ROOT_INFO_INVALID;
>
> optional: Consider open-coding this directly in kvm_mmu_create() and
> drop __kvm_mmu_create().

__kvm_mmu_create() is kept, and I don't want to duplicate this code.

> >  }
> >
> >  int kvm_mmu_create(struct kvm_vcpu *vcpu)
>
> kvm_mmu_create() could return void now too.

Did in v3.

Thanks
Lai