Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752711AbdLHRbX (ORCPT ); Fri, 8 Dec 2017 12:31:23 -0500 Received: from mail-it0-f68.google.com ([209.85.214.68]:41680 "EHLO mail-it0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752447AbdLHRbU (ORCPT ); Fri, 8 Dec 2017 12:31:20 -0500 X-Google-Smtp-Source: AGs4zMZDm0eq8R+BptSUIQIKwHJlitc4d4N2KW+2cAbBWj3uHROHDDaYpyyfjeSINR/IBF1YNpAKgPmllsRe1FcQE2c= MIME-Version: 1.0 In-Reply-To: <1512728546-4365-1-git-send-email-quan.xu0@gmail.com> References: <1512728546-4365-1-git-send-email-quan.xu0@gmail.com> From: Jim Mattson Date: Fri, 8 Dec 2017 09:31:18 -0800 Message-ID: Subject: Re: [PATCH] KVM: VMX: drop I/O permission bitmaps To: Quan Xu Cc: kvm list , LKML , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Paolo Bonzini Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by nfs id vB8HWErM020143 Content-Length: 3471 Lines: 85 On Fri, Dec 8, 2017 at 2:22 AM, Quan Xu wrote: > From: Quan Xu > > Since KVM removes the only I/O port 0x80 bypass on Intel hosts, > clear CPU_BASED_USE_IO_BITMAPS and set CPU_BASED_UNCOND_IO_EXITING > bit. Then these I/O permission bitmaps are not used at all, so > drop I/O permission bitmaps. > > Signed-off-by: Jim Mattson > Signed-off-by: Radim Krčmář > Signed-off-by: Quan Xu > --- > arch/x86/kvm/vmx.c | 17 +---------------- > 1 files changed, 1 insertions(+), 16 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index 2fd9a8c..3e4f760 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -771,8 +771,6 @@ enum segment_cache_field { > FIELD(HOST_FS_SELECTOR, host_fs_selector), > FIELD(HOST_GS_SELECTOR, host_gs_selector), > FIELD(HOST_TR_SELECTOR, host_tr_selector), > - FIELD64(IO_BITMAP_A, io_bitmap_a), > - FIELD64(IO_BITMAP_B, io_bitmap_b), These two lines should stay. > FIELD64(MSR_BITMAP, msr_bitmap), > FIELD64(VM_EXIT_MSR_STORE_ADDR, vm_exit_msr_store_addr), > FIELD64(VM_EXIT_MSR_LOAD_ADDR, vm_exit_msr_load_addr), > @@ -943,8 +941,6 @@ static bool nested_vmx_is_page_fault_vmexit(struct vmcs12 *vmcs12, > static DEFINE_PER_CPU(spinlock_t, blocked_vcpu_on_cpu_lock); > > enum { > - VMX_IO_BITMAP_A, > - VMX_IO_BITMAP_B, > VMX_MSR_BITMAP_LEGACY, > VMX_MSR_BITMAP_LONGMODE, > VMX_MSR_BITMAP_LEGACY_X2APIC_APICV, > @@ -958,8 +954,6 @@ enum { > > static unsigned long *vmx_bitmap[VMX_BITMAP_NR]; > > -#define vmx_io_bitmap_a (vmx_bitmap[VMX_IO_BITMAP_A]) > -#define vmx_io_bitmap_b (vmx_bitmap[VMX_IO_BITMAP_B]) > #define vmx_msr_bitmap_legacy (vmx_bitmap[VMX_MSR_BITMAP_LEGACY]) > #define vmx_msr_bitmap_longmode (vmx_bitmap[VMX_MSR_BITMAP_LONGMODE]) > #define vmx_msr_bitmap_legacy_x2apic_apicv (vmx_bitmap[VMX_MSR_BITMAP_LEGACY_X2APIC_APICV]) > @@ -3632,7 +3626,7 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf) > #endif > CPU_BASED_CR3_LOAD_EXITING | > CPU_BASED_CR3_STORE_EXITING | > - CPU_BASED_USE_IO_BITMAPS | > + CPU_BASED_UNCOND_IO_EXITING | > CPU_BASED_MOV_DR_EXITING | > CPU_BASED_USE_TSC_OFFSETING | > CPU_BASED_INVLPG_EXITING | > @@ -5445,10 +5439,6 @@ static void vmx_vcpu_setup(struct vcpu_vmx *vmx) > #endif > int i; > > - /* I/O */ > - vmcs_write64(IO_BITMAP_A, __pa(vmx_io_bitmap_a)); > - vmcs_write64(IO_BITMAP_B, __pa(vmx_io_bitmap_b)); > - > if (enable_shadow_vmcs) { > vmcs_write64(VMREAD_BITMAP, __pa(vmx_vmread_bitmap)); > vmcs_write64(VMWRITE_BITMAP, __pa(vmx_vmwrite_bitmap)); > @@ -6751,14 +6741,9 @@ static __init int hardware_setup(void) > goto out; > } > > - vmx_io_bitmap_b = (unsigned long *)__get_free_page(GFP_KERNEL); > memset(vmx_vmread_bitmap, 0xff, PAGE_SIZE); > memset(vmx_vmwrite_bitmap, 0xff, PAGE_SIZE); > > - memset(vmx_io_bitmap_a, 0xff, PAGE_SIZE); > - > - memset(vmx_io_bitmap_b, 0xff, PAGE_SIZE); > - > memset(vmx_msr_bitmap_legacy, 0xff, PAGE_SIZE); > memset(vmx_msr_bitmap_longmode, 0xff, PAGE_SIZE); > > -- > 1.7.1 >