Il 20/08/2014 11:45, Wanpeng Li ha scritto: > Introduce apic_access_and_virtual_page_valid() to check the valid > of nested apic access page and virtual apic page earlier. > > Signed-off-by: Wanpeng Li <wanpeng.li@xxxxxxxxxxxxxxx> > --- > arch/x86/kvm/vmx.c | 82 ++++++++++++++++++++++++++++++------------------------ > 1 file changed, 46 insertions(+), 36 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index caf239d..02bc07d 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -7838,6 +7838,50 @@ static void vmx_inject_page_fault_nested(struct kvm_vcpu *vcpu, > kvm_inject_page_fault(vcpu, fault); > } > > +static bool apic_access_and_virtual_page_valid(struct kvm_vcpu *vcpu, > + struct vmcs12 *vmcs12) > +{ > + struct vcpu_vmx *vmx = to_vmx(vcpu); > + > + if (nested_cpu_has2(vmcs12, SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)) { > + if (!PAGE_ALIGNED(vmcs12->apic_access_addr)) > + /*TODO: Also verify bits beyond physical address width are 0*/ > + return false; > + > + /* > + * Translate L1 physical address to host physical > + * address for vmcs02. Keep the page pinned, so this > + * physical address remains valid. We keep a reference > + * to it so we can release it later. > + */ > + if (vmx->nested.apic_access_page) /* shouldn't happen */ > + nested_release_page(vmx->nested.apic_access_page); > + vmx->nested.apic_access_page = > + nested_get_page(vcpu, vmcs12->apic_access_addr); > + } > + > + if (nested_cpu_has(vmcs12, CPU_BASED_TPR_SHADOW)) { > + if (vmx->nested.virtual_apic_page) /* shouldn't happen */ > + nested_release_page(vmx->nested.virtual_apic_page); > + vmx->nested.virtual_apic_page = > + nested_get_page(vcpu, vmcs12->virtual_apic_page_addr); > + > + /* > + * Failing the vm entry is _not_ what the processor does > + * but it's basically the only possibility we have. > + * We could still enter the guest if CR8 load exits are > + * enabled, CR8 store exits are enabled, and virtualize APIC > + * access is disabled; in this case the processor would never > + * use the TPR shadow and we could simply clear the bit from > + * the execution control. But such a configuration is useless, > + * so let's keep the code simple. > + */ > + if (!vmx->nested.virtual_apic_page) > + return false; > + } > + return true; > +} > + > static void vmx_start_preemption_timer(struct kvm_vcpu *vcpu) > { > u64 preemption_timeout = get_vmcs12(vcpu)->vmx_preemption_timer_value; > @@ -7984,16 +8028,6 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) > > if (exec_control & SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES) { > /* > - * Translate L1 physical address to host physical > - * address for vmcs02. Keep the page pinned, so this > - * physical address remains valid. We keep a reference > - * to it so we can release it later. > - */ > - if (vmx->nested.apic_access_page) /* shouldn't happen */ > - nested_release_page(vmx->nested.apic_access_page); > - vmx->nested.apic_access_page = > - nested_get_page(vcpu, vmcs12->apic_access_addr); > - /* > * If translation failed, no matter: This feature asks > * to exit when accessing the given address, and if it > * can never be accessed, this feature won't do > @@ -8040,30 +8074,8 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) > exec_control |= vmcs12->cpu_based_vm_exec_control; > > if (exec_control & CPU_BASED_TPR_SHADOW) { > - if (vmx->nested.virtual_apic_page) > - nested_release_page(vmx->nested.virtual_apic_page); > - vmx->nested.virtual_apic_page = > - nested_get_page(vcpu, vmcs12->virtual_apic_page_addr); > - if (!vmx->nested.virtual_apic_page) > - exec_control &= > - ~CPU_BASED_TPR_SHADOW; > - else > - vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, > + vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, > page_to_phys(vmx->nested.virtual_apic_page)); > - > - /* > - * Failing the vm entry is _not_ what the processor does > - * but it's basically the only possibility we have. > - * We could still enter the guest if CR8 load exits are > - * enabled, CR8 store exits are enabled, and virtualize APIC > - * access is disabled; in this case the processor would never > - * use the TPR shadow and we could simply clear the bit from > - * the execution control. But such a configuration is useless, > - * so let's keep the code simple. > - */ > - if (!vmx->nested.virtual_apic_page) > - nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD); > - > vmcs_write32(TPR_THRESHOLD, vmcs12->tpr_threshold); > } else if (vm_need_tpr_shadow(vmx->vcpu.kvm)) > vmcs_write64(VIRTUAL_APIC_PAGE_ADDR, > @@ -8230,9 +8242,7 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) > return 1; > } > > - if (nested_cpu_has2(vmcs12, SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES) && > - !PAGE_ALIGNED(vmcs12->apic_access_addr)) { > - /*TODO: Also verify bits beyond physical address width are 0*/ > + if (!apic_access_and_virtual_page_valid(vcpu, vmcs12)) { > nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD); > return 1; > } > Thanks Wanpeng. The code now looks good. Just one thing: please swap them, so that the series remains bisectable. Also, I think nested_get_vmcs12_pages would be a better name for the function. apic_access_and_virtual_page_valid doesn't hint at the side effects of the function (for example calling nested_get_page). The way I swap patches is by using "git checkout -p" like this: git branch tpr-shadow-old git reset --hard HEAD^^ git checkout -p tpr-shadow-old ... pick hunks related to the second patch ... git commit -c tpr-shadow-old ... edit commit message if needed ... git checkout -p tpr-shadow-old ... pick hunks related to the first patch ... git commit -C tpr-shadow-old^ ... edit commit message if needed ... git diff tpr-shadow-old HEAD Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html