| Message ID | 80fcaae4-ea5b-faac-5695-cd7188ac3bf0@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 2017/12/09 00:18, David Hildenbrand wrote: > On 08.12.2017 11:22, Quan Xu wrote: >> From: Quan Xu <quan.xu0@gmail.com> >> >> 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 <jmattson@google.com> >> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> >> Signed-off-by: Quan Xu <quan.xu0@gmail.com> >> --- >> 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), >> 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); >> >> > Looks good to me. David, thanks for your review. > > We could now also drop > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index a5d2856eb28b..732e93332f4c 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -10639,7 +10639,6 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, > struct vmcs12 *vmcs12, > * Rather, exit every time. > */ > exec_control &= ~CPU_BASED_USE_IO_BITMAPS; > - exec_control |= CPU_BASED_UNCOND_IO_EXITING; > > vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, exec_control); > > As this will be implicitly set by vmx_exec_control() > good catch. yes, L0 merge vmcs01 with vmcsl2 to create vmcs02 and run L2. however as this code is related to nested virtualization, I better introduce it in another new patch with "KVM: NVMX" prefix subject after this patch is applied. furthermore, I think I could drop these tow lines in another new patch: - exec_control &= ~CPU_BASED_USE_IO_BITMAPS; - exec_control |= CPU_BASED_UNCOND_IO_EXITING; as the CPU_BASED_USE_IO_BITMAPS is clear after this patch. Quan
On 2017/12/09 00:18, David Hildenbrand wrote: > On 08.12.2017 11:22, Quan Xu wrote: >> From: Quan Xu <quan.xu0@gmail.com> >> >> 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 <jmattson@google.com> >> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> >> Signed-off-by: Quan Xu <quan.xu0@gmail.com> >> --- >> 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), >> 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); >> >> > Looks good to me. > > We could now also drop > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index a5d2856eb28b..732e93332f4c 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -10639,7 +10639,6 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, > struct vmcs12 *vmcs12, > * Rather, exit every time. > */ > exec_control &= ~CPU_BASED_USE_IO_BITMAPS; > - exec_control |= CPU_BASED_UNCOND_IO_EXITING; > > vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, exec_control); > > As this will be implicitly set by vmx_exec_control() David, I find some nVMX code is still using vmcs12 (.e.g. nested_cpu_has(vmcs12, CPU_BASED_USE_IO_BITMAPS)) dropping it would make these logic error handling.. we better leave it as is.. Quan Alibaba Cloud >
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index a5d2856eb28b..732e93332f4c 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -10639,7 +10639,6 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, * Rather, exit every time. */ exec_control &= ~CPU_BASED_USE_IO_BITMAPS; - exec_control |= CPU_BASED_UNCOND_IO_EXITING; vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, exec_control);