On Mon, Jul 08, 2013 at 07:12:35PM +0800, Arthur Chunqi Li wrote: > From: Nadav Har'El <nyh@xxxxxxxxxxxxxxxxxxx> > > Fix read/write to IA32_FEATURE_CONTROL MSR in nested environment. > > This patch simulate this MSR in nested_vmx and the default value is > 0x0. BIOS should set it to 0x5 before VMXON. After setting the lock > bit, write to it will cause #GP(0). > > Another QEMU patch is also needed to handle emulation of reset > and migration. Reset to vCPU should clear this MSR and migration > should reserve value of it. > > This patch is based on Nadav's previous commit. > http://permalink.gmane.org/gmane.comp.emulators.kvm.devel/88478 > > Signed-off-by: Nadav Har'El <nyh@xxxxxxxxxxxxxxxxxxx> > Signed-off-by: Arthur Chunqi Li <yzt356@xxxxxxxxx> Applied, thanks. > --- > arch/x86/kvm/vmx.c | 35 +++++++++++++++++++++++++++++------ > arch/x86/kvm/x86.c | 3 ++- > 2 files changed, 31 insertions(+), 7 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index a7e1855..1200e4e 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -373,6 +373,7 @@ struct nested_vmx { > * we must keep them pinned while L2 runs. > */ > struct page *apic_access_page; > + u64 msr_ia32_feature_control; > }; > > #define POSTED_INTR_ON 0 > @@ -2282,8 +2283,11 @@ static int vmx_get_vmx_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata) > > switch (msr_index) { > case MSR_IA32_FEATURE_CONTROL: > - *pdata = 0; > - break; > + if (nested_vmx_allowed(vcpu)) { > + *pdata = to_vmx(vcpu)->nested.msr_ia32_feature_control; > + break; > + } > + return 0; > case MSR_IA32_VMX_BASIC: > /* > * This MSR reports some information about VMX support. We > @@ -2356,14 +2360,24 @@ static int vmx_get_vmx_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata) > return 1; > } > > -static int vmx_set_vmx_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data) > +static int vmx_set_vmx_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > { > + u32 msr_index = msr_info->index; > + u64 data = msr_info->data; > + bool host_initialized = msr_info->host_initiated; > + > if (!nested_vmx_allowed(vcpu)) > return 0; > > - if (msr_index == MSR_IA32_FEATURE_CONTROL) > - /* TODO: the right thing. */ > + if (msr_index == MSR_IA32_FEATURE_CONTROL) { > + if (!host_initialized && > + to_vmx(vcpu)->nested.msr_ia32_feature_control > + & FEATURE_CONTROL_LOCKED) > + return 0; > + to_vmx(vcpu)->nested.msr_ia32_feature_control = data; > return 1; > + } > + > /* > * No need to treat VMX capability MSRs specially: If we don't handle > * them, handle_wrmsr will #GP(0), which is correct (they are readonly) > @@ -2494,7 +2508,7 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > return 1; > /* Otherwise falls through */ > default: > - if (vmx_set_vmx_msr(vcpu, msr_index, data)) > + if (vmx_set_vmx_msr(vcpu, msr_info)) > break; > msr = find_msr_entry(vmx, msr_index); > if (msr) { > @@ -5576,6 +5590,8 @@ static int handle_vmon(struct kvm_vcpu *vcpu) > struct kvm_segment cs; > struct vcpu_vmx *vmx = to_vmx(vcpu); > struct vmcs *shadow_vmcs; > + const u64 VMXON_NEEDED_FEATURES = FEATURE_CONTROL_LOCKED > + | FEATURE_CONTROL_VMXON_ENABLED_OUTSIDE_SMX; > > /* The Intel VMX Instruction Reference lists a bunch of bits that > * are prerequisite to running VMXON, most notably cr4.VMXE must be > @@ -5604,6 +5620,13 @@ static int handle_vmon(struct kvm_vcpu *vcpu) > skip_emulated_instruction(vcpu); > return 1; > } > + > + if ((vmx->nested.msr_ia32_feature_control & VMXON_NEEDED_FEATURES) > + != VMXON_NEEDED_FEATURES) { > + kvm_inject_gp(vcpu, 0); > + return 1; > + } > + > if (enable_shadow_vmcs) { > shadow_vmcs = alloc_vmcs(); > if (!shadow_vmcs) > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index d21bce5..cff77c4 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -850,7 +850,8 @@ static u32 msrs_to_save[] = { > #ifdef CONFIG_X86_64 > MSR_CSTAR, MSR_KERNEL_GS_BASE, MSR_SYSCALL_MASK, MSR_LSTAR, > #endif > - MSR_IA32_TSC, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA > + MSR_IA32_TSC, MSR_IA32_CR_PAT, MSR_VM_HSAVE_PA, > + MSR_IA32_FEATURE_CONTROL > }; > > static unsigned num_msrs_to_save; > -- > 1.7.9.5 -- Gleb. -- 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
