Re: [Qemu-devel] [PATCH 3/4] KVM/X86: Intel MPX vmx and msr handle

[Paolo Bonzini]

Il 02/12/2013 17:46, Liu, Jinsong ha scritto:
> From e9ba40b3d1820b8ab31431c73226ee3ed485edd1 Mon Sep 17 00:00:00 2001
> From: Liu Jinsong <address@hidden>
> Date: Tue, 3 Dec 2013 07:02:27 +0800
> Subject: [PATCH 3/4] KVM/X86: Intel MPX vmx and msr handle
> 
> Signed-off-by: Xudong Hao <address@hidden>
> Signed-off-by: Liu Jinsong <address@hidden>
> ---
>  arch/x86/include/asm/vmx.h            |    2 ++
>  arch/x86/include/uapi/asm/msr-index.h |    1 +
>  arch/x86/kvm/vmx.c                    |   12 ++++++++++--
>  3 files changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
> index 966502d..1bf4681 100644
> --- a/arch/x86/include/asm/vmx.h
> +++ b/arch/x86/include/asm/vmx.h
> @@ -85,6 +85,7 @@
>  #define VM_EXIT_SAVE_IA32_EFER                  0x00100000
>  #define VM_EXIT_LOAD_IA32_EFER                  0x00200000
>  #define VM_EXIT_SAVE_VMX_PREEMPTION_TIMER       0x00400000
> +#define VM_EXIT_CLEAR_BNDCFGS                   0x00800000
>  
>  #define VM_EXIT_ALWAYSON_WITHOUT_TRUE_MSR    0x00036dff
>  
> @@ -95,6 +96,7 @@
>  #define VM_ENTRY_LOAD_IA32_PERF_GLOBAL_CTRL     0x00002000
>  #define VM_ENTRY_LOAD_IA32_PAT                       0x00004000
>  #define VM_ENTRY_LOAD_IA32_EFER                 0x00008000
> +#define VM_ENTRY_LOAD_BNDCFGS                   0x00010000
>  
>  #define VM_ENTRY_ALWAYSON_WITHOUT_TRUE_MSR   0x000011ff
>  
> diff --git a/arch/x86/include/uapi/asm/msr-index.h 
> b/arch/x86/include/uapi/asm/msr-index.h
> index 37813b5..2a418c4 100644
> --- a/arch/x86/include/uapi/asm/msr-index.h
> +++ b/arch/x86/include/uapi/asm/msr-index.h
> @@ -294,6 +294,7 @@
>  #define MSR_SMI_COUNT                        0x00000034
>  #define MSR_IA32_FEATURE_CONTROL        0x0000003a
>  #define MSR_IA32_TSC_ADJUST             0x0000003b
> +#define MSR_IA32_BNDCFGS             0x00000d90
>  
>  #define FEATURE_CONTROL_LOCKED                               (1<<0)
>  #define FEATURE_CONTROL_VMXON_ENABLED_INSIDE_SMX     (1<<1)
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index b2fe1c2..9a16e60 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -439,6 +439,7 @@ struct vcpu_vmx {
>  #endif
>               int           gs_ldt_reload_needed;
>               int           fs_reload_needed;
> +             u64           msr_host_bndcfgs;
>       } host_state;
>       struct {
>               int vm86_active;
> @@ -1647,6 +1648,8 @@ static void vmx_save_host_state(struct kvm_vcpu *vcpu)
>       if (is_long_mode(&vmx->vcpu))
>               wrmsrl(MSR_KERNEL_GS_BASE, vmx->msr_guest_kernel_gs_base);
>  #endif
> +     if (cpu_has_mpx)
> +             rdmsrl(MSR_IA32_BNDCFGS, vmx->host_state.msr_host_bndcfgs);
>       for (i = 0; i < vmx->save_nmsrs; ++i)
>               kvm_set_shared_msr(vmx->guest_msrs[i].index,
>                                  vmx->guest_msrs[i].data,
> @@ -1684,6 +1687,8 @@ static void __vmx_load_host_state(struct vcpu_vmx *vmx)
>  #ifdef CONFIG_X86_64
>       wrmsrl(MSR_KERNEL_GS_BASE, vmx->msr_host_kernel_gs_base);
>  #endif
> +     if (vmx->host_state.msr_host_bndcfgs)
> +             wrmsrl(MSR_IA32_BNDCFGS, vmx->host_state.msr_host_bndcfgs);
>       /*
>        * If the FPU is not active (through the host task or
>        * the guest vcpu), then restore the cr0.TS bit.
> @@ -2800,7 +2805,7 @@ static __init int setup_vmcs_config(struct vmcs_config 
> *vmcs_conf)
>       min |= VM_EXIT_HOST_ADDR_SPACE_SIZE;
>  #endif
>       opt = VM_EXIT_SAVE_IA32_PAT | VM_EXIT_LOAD_IA32_PAT |
> -             VM_EXIT_ACK_INTR_ON_EXIT;
> +             VM_EXIT_ACK_INTR_ON_EXIT | VM_EXIT_CLEAR_BNDCFGS;
>       if (adjust_vmx_controls(min, opt, MSR_IA32_VMX_EXIT_CTLS,
>                               &_vmexit_control) < 0)
>               return -EIO;
> @@ -2817,7 +2822,7 @@ static __init int setup_vmcs_config(struct vmcs_config 
> *vmcs_conf)
>               _pin_based_exec_control &= ~PIN_BASED_POSTED_INTR;
>  
>       min = 0;
> -     opt = VM_ENTRY_LOAD_IA32_PAT;
> +     opt = VM_ENTRY_LOAD_IA32_PAT | VM_ENTRY_LOAD_BNDCFGS;
>       if (adjust_vmx_controls(min, opt, MSR_IA32_VMX_ENTRY_CTLS,
>                               &_vmentry_control) < 0)
>               return -EIO;
> @@ -8636,6 +8641,9 @@ static int __init vmx_init(void)
>       vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_CS, false);
>       vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_ESP, false);
>       vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_EIP, false);
> +     if (cpu_has_mpx)
> +             vmx_disable_intercept_for_msr(MSR_IA32_BNDCFGS, true);
> +
>       memcpy(vmx_msr_bitmap_legacy_x2apic,
>                       vmx_msr_bitmap_legacy, PAGE_SIZE);
>       memcpy(vmx_msr_bitmap_longmode_x2apic,
> 

This patch should also add BNDCFGS to msrs_to_save, in arch/x86/kvm/x86.c.

Paolo