2012-08-31 16:11:33

by Davidlohr Bueso

Subject: [PATCH] KVM: VMX: invalidate vpid for invlpg instruction

For processors that support VPIDs we should invalidate the page table entry
specified by the lineal address. For this purpose add support for individual
address invalidations.

Signed-off-by: Davidlohr Bueso <[email protected]>
---
arch/x86/include/asm/vmx.h | 6 ++++--
arch/x86/kvm/vmx.c | 15 +++++++++++++++
2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index 74fcb96..20abb18 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -393,6 +393,7 @@ enum vmcs_field {
#define IDENTITY_PAGETABLE_PRIVATE_MEMSLOT (KVM_MEMORY_SLOTS + 2)

#define VMX_NR_VPIDS (1 << 16)
+#define VMX_VPID_EXTENT_INDIVIDUAL_ADDR 0
#define VMX_VPID_EXTENT_SINGLE_CONTEXT 1
#define VMX_VPID_EXTENT_ALL_CONTEXT 2

@@ -406,12 +407,13 @@ enum vmcs_field {
#define VMX_EPTP_WB_BIT (1ull << 14)
#define VMX_EPT_2MB_PAGE_BIT (1ull << 16)
#define VMX_EPT_1GB_PAGE_BIT (1ull << 17)
-#define VMX_EPT_AD_BIT (1ull << 21)
+#define VMX_EPT_AD_BIT (1ull << 21)
#define VMX_EPT_EXTENT_INDIVIDUAL_BIT (1ull << 24)
#define VMX_EPT_EXTENT_CONTEXT_BIT (1ull << 25)
#define VMX_EPT_EXTENT_GLOBAL_BIT (1ull << 26)

-#define VMX_VPID_EXTENT_SINGLE_CONTEXT_BIT (1ull << 9) /* (41 - 32) */
+#define VMX_VPID_EXTENT_INDIVIDUAL_ADDR_BIT (1ull << 8) /* (40 - 32) */
+#define VMX_VPID_EXTENT_SINGLE_CONTEXT_BIT (1ull << 9) /* (41 - 32) */
#define VMX_VPID_EXTENT_GLOBAL_CONTEXT_BIT (1ull << 10) /* (42 - 32) */

#define VMX_EPT_DEFAULT_GAW 3
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index c00f03d..d87b22c 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -816,6 +816,11 @@ static inline bool cpu_has_vmx_invept_global(void)
return vmx_capability.ept & VMX_EPT_EXTENT_GLOBAL_BIT;
}

+static inline bool cpu_has_vmx_invvpid_individual_addr(void)
+{
+ return vmx_capability.vpid & VMX_VPID_EXTENT_INDIVIDUAL_ADDR_BIT;
+}
+
static inline bool cpu_has_vmx_invvpid_single(void)
{
return vmx_capability.vpid & VMX_VPID_EXTENT_SINGLE_CONTEXT_BIT;
@@ -1011,6 +1016,15 @@ static void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs)
loaded_vmcs->cpu, __loaded_vmcs_clear, loaded_vmcs, 1);
}

+static inline void vpid_sync_vcpu_individual_addr(struct vcpu_vmx *vmx, gpa_t gpa)
+{
+ if (vmx->vpid == 0)
+ return;
+
+ if (cpu_has_vmx_invvpid_individual_addr())
+ __invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR, vmx->vpid, gpa);
+}
+
static inline void vpid_sync_vcpu_single(struct vcpu_vmx *vmx)
{
if (vmx->vpid == 0)
@@ -4719,6 +4733,7 @@ static int handle_invlpg(struct kvm_vcpu *vcpu)
unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);

kvm_mmu_invlpg(vcpu, exit_qualification);
+ vpid_sync_vcpu_individual_addr(to_vmx(vcpu), exit_qualification);
skip_emulated_instruction(vcpu);
return 1;
}
--
1.7.4.1

2012-08-31 17:37:14

by Marcelo Tosatti

Subject: Re: [PATCH] KVM: VMX: invalidate vpid for invlpg instruction

On Fri, Aug 31, 2012 at 06:10:48PM +0200, Davidlohr Bueso wrote:
> For processors that support VPIDs we should invalidate the page table entry
> specified by the lineal address. For this purpose add support for individual
> address invalidations.

Not necessary - a single context invalidation is performed through
KVM_REQ_TLB_FLUSH.

Single-context. If the INVVPID type is 1, the logical processor
invalidates all
linear mappings and combined mappings associated with the VPID specified
in the INVVPID descriptor.