From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gleb Natapov Subject: Re: [PATCH v3 1/7] KVM: MMU: fix release noslot pfn Date: Sun, 23 Sep 2012 11:13:35 +0200 Message-ID: <20120923091335.GA20907@redhat.com> References: <505C0FA8.5070007@linux.vnet.ibm.com> <505C0FCF.2070308@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Avi Kivity , Marcelo Tosatti , LKML , KVM To: Xiao Guangrong Return-path: Received: from mx1.redhat.com ([209.132.183.28]:13073 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752964Ab2IWJNi (ORCPT ); Sun, 23 Sep 2012 05:13:38 -0400 Content-Disposition: inline In-Reply-To: <505C0FCF.2070308@linux.vnet.ibm.com> Sender: kvm-owner@vger.kernel.org List-ID: On Fri, Sep 21, 2012 at 02:57:19PM +0800, Xiao Guangrong wrote: > We can not directly call kvm_release_pfn_clean to release the pfn > since we can meet noslot pfn which is used to cache mmio info into > spte > Wouldn't it be better to move the check into kvm_release_pfn_clean()? > Signed-off-by: Xiao Guangrong > --- > arch/x86/kvm/mmu.c | 6 ++++-- > arch/x86/kvm/paging_tmpl.h | 6 ++++-- > 2 files changed, 8 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c > index aa0b469..0f56169 100644 > --- a/arch/x86/kvm/mmu.c > +++ b/arch/x86/kvm/mmu.c > @@ -2877,7 +2877,8 @@ static int nonpaging_map(struct kvm_vcpu *vcpu, gva_t v, u32 error_code, > > out_unlock: > spin_unlock(&vcpu->kvm->mmu_lock); > - kvm_release_pfn_clean(pfn); > + if (likely(!is_noslot_pfn(pfn))) > + kvm_release_pfn_clean(pfn); > return 0; > } > > @@ -3345,7 +3346,8 @@ static int tdp_page_fault(struct kvm_vcpu *vcpu, gva_t gpa, u32 error_code, > > out_unlock: > spin_unlock(&vcpu->kvm->mmu_lock); > - kvm_release_pfn_clean(pfn); > + if (likely(!is_noslot_pfn(pfn))) > + kvm_release_pfn_clean(pfn); > return 0; > } > > diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h > index bf8c42b..9ce6bc0 100644 > --- a/arch/x86/kvm/paging_tmpl.h > +++ b/arch/x86/kvm/paging_tmpl.h > @@ -544,7 +544,8 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr, > out_gpte_changed: > if (sp) > kvm_mmu_put_page(sp, it.sptep); > - kvm_release_pfn_clean(pfn); > + if (likely(!is_noslot_pfn(pfn))) > + kvm_release_pfn_clean(pfn); > return NULL; > } > > @@ -645,7 +646,8 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gva_t addr, u32 error_code, > > out_unlock: > spin_unlock(&vcpu->kvm->mmu_lock); > - kvm_release_pfn_clean(pfn); > + if (likely(!is_noslot_pfn(pfn))) > + kvm_release_pfn_clean(pfn); > return 0; > } > > -- > 1.7.7.6 > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Gleb.