From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932373AbbFQPk4 (ORCPT ); Wed, 17 Jun 2015 11:40:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44986 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757918AbbFQPkv (ORCPT ); Wed, 17 Jun 2015 11:40:51 -0400 Message-ID: <558194FE.6050509@redhat.com> Date: Wed, 17 Jun 2015 17:40:46 +0200 From: Paolo Bonzini User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Xiao Guangrong CC: gleb@kernel.org, mtosatti@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, dmatlack@google.com Subject: Re: [PATCH v2 11/15] KVM: MTRR: sort variable MTRRs References: <1434358535-19923-1-git-send-email-guangrong.xiao@linux.intel.com> <1434358535-19923-12-git-send-email-guangrong.xiao@linux.intel.com> In-Reply-To: <1434358535-19923-12-git-send-email-guangrong.xiao@linux.intel.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 15/06/2015 10:55, Xiao Guangrong wrote: > Sort all valid variable MTRRs based on its base address, it will help us to > check a range to see if it's fully contained in variable MTRRs > > Signed-off-by: Xiao Guangrong > --- > arch/x86/include/asm/kvm_host.h | 3 ++ > arch/x86/kvm/mtrr.c | 63 ++++++++++++++++++++++++++++++++++------- > arch/x86/kvm/x86.c | 2 +- > arch/x86/kvm/x86.h | 1 + > 4 files changed, 58 insertions(+), 11 deletions(-) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index f735548..f2d60cc 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -345,12 +345,15 @@ enum { > struct kvm_mtrr_range { > u64 base; > u64 mask; > + struct list_head node; > }; > > struct kvm_mtrr { > struct kvm_mtrr_range var_ranges[KVM_NR_VAR_MTRR]; > mtrr_type fixed_ranges[KVM_NR_FIXED_MTRR_REGION]; > u64 deftype; > + > + struct list_head head; > }; > > struct kvm_vcpu_arch { > diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c > index cb9702d..c06ec13 100644 > --- a/arch/x86/kvm/mtrr.c > +++ b/arch/x86/kvm/mtrr.c > @@ -281,6 +281,52 @@ static void update_mtrr(struct kvm_vcpu *vcpu, u32 msr) > kvm_zap_gfn_range(vcpu->kvm, gpa_to_gfn(start), gpa_to_gfn(end)); > } > > +static bool var_mtrr_range_is_valid(struct kvm_mtrr_range *range) > +{ > + u64 start, end; > + > + if (!(range->mask & (1 << 11))) > + return false; > + > + var_mtrr_range(range, &start, &end); > + return end > start; > +} I think this test is incorrect; it is always true unless end overflows to zero, which cannot happen because writing an invalid value to the MSR causes a #GP. Paolo > +static void set_var_mtrr_start(struct kvm_mtrr *mtrr_state, int index) > +{ > + /* remove the entry if it's in the list. */ > + if (var_mtrr_range_is_valid(&mtrr_state->var_ranges[index])) > + list_del(&mtrr_state->var_ranges[index].node); > +} > + > +static void set_var_mtrr_end(struct kvm_mtrr *mtrr_state, int index) > +{ > + struct kvm_mtrr_range *tmp, *cur = &mtrr_state->var_ranges[index]; > + > + /* add it to the list if it's valid. */ > + if (var_mtrr_range_is_valid(&mtrr_state->var_ranges[index])) { > + list_for_each_entry(tmp, &mtrr_state->head, node) > + if (cur->base < tmp->base) > + list_add_tail(&cur->node, &tmp->node); > + > + list_add_tail(&cur->node, &mtrr_state->head); > + } > +} > + > +static void set_var_mtrr_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data) > +{ > + int index, is_mtrr_mask; > + > + index = (msr - 0x200) / 2; > + is_mtrr_mask = msr - 0x200 - 2 * index; > + set_var_mtrr_start(&vcpu->arch.mtrr_state, index); > + if (!is_mtrr_mask) > + vcpu->arch.mtrr_state.var_ranges[index].base = data; > + else > + vcpu->arch.mtrr_state.var_ranges[index].mask = data; > + set_var_mtrr_end(&vcpu->arch.mtrr_state, index); > +} > + > int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data) > { > int index; > @@ -295,16 +341,8 @@ int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data) > vcpu->arch.mtrr_state.deftype = data; > else if (msr == MSR_IA32_CR_PAT) > vcpu->arch.pat = data; > - else { /* Variable MTRRs */ > - int is_mtrr_mask; > - > - index = (msr - 0x200) / 2; > - is_mtrr_mask = msr - 0x200 - 2 * index; > - if (!is_mtrr_mask) > - vcpu->arch.mtrr_state.var_ranges[index].base = data; > - else > - vcpu->arch.mtrr_state.var_ranges[index].mask = data; > - } > + else > + set_var_mtrr_msr(vcpu, msr, data); > > update_mtrr(vcpu, msr); > return 0; > @@ -350,6 +388,11 @@ int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata) > return 0; > } > > +void kvm_vcpu_mtrr_init(struct kvm_vcpu *vcpu) > +{ > + INIT_LIST_HEAD(&vcpu->arch.mtrr_state.head); > +} > + > u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn) > { > struct kvm_mtrr *mtrr_state = &vcpu->arch.mtrr_state; > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 2ffad7f..6574fa3 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -7379,13 +7379,13 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) > { > int r; > > + kvm_vcpu_mtrr_init(vcpu); > r = vcpu_load(vcpu); > if (r) > return r; > kvm_vcpu_reset(vcpu, false); > kvm_mmu_setup(vcpu); > vcpu_put(vcpu); > - > return r; > } > > diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h > index aeb0bb2..0e4727c 100644 > --- a/arch/x86/kvm/x86.h > +++ b/arch/x86/kvm/x86.h > @@ -162,6 +162,7 @@ int kvm_write_guest_virt_system(struct x86_emulate_ctxt *ctxt, > gva_t addr, void *val, unsigned int bytes, > struct x86_exception *exception); > > +void kvm_vcpu_mtrr_init(struct kvm_vcpu *vcpu); > u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn); > bool kvm_mtrr_valid(struct kvm_vcpu *vcpu, u32 msr, u64 data); > int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data); >