This needs a minor bug fix. The updated patch is as follows.
Thanks,
Junaid
------------------------------------------------------------------------------
kvm_mmu_invlpg() and kvm_mmu_invpcid_gva() only need to flush the TLB
entries for the specific guest virtual address, instead of flushing all
TLB entries associated with the VM.
Signed-off-by: Junaid Shahid <junaids@xxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 8 ++++++++
arch/x86/kvm/mmu.c | 10 ++++++---
arch/x86/kvm/svm.c | 8 ++++++++
arch/x86/kvm/vmx.c | 36 +++++++++++++++++++++++++++++++++
4 files changed, 59 insertions(+), 3 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index e313e457dcbc..f50de601afd8 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -984,6 +984,14 @@ struct kvm_x86_ops {
void (*tlb_flush)(struct kvm_vcpu *vcpu, bool invalidate_gpa);
+ /*
+ * Flush any TLB entries associated with the given GVA.
+ * Does not need to flush GPA->HPA mappings.
+ * Can potentially get non-canonical addresses through INVLPGs, which
+ * the implementation may choose to ignore if appropriate.
+ */
+ void (*tlb_flush_gva)(struct kvm_vcpu *vcpu, gva_t addr);
+
void (*run)(struct kvm_vcpu *vcpu);
int (*handle_exit)(struct kvm_vcpu *vcpu);
void (*skip_emulated_instruction)(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 9446a36a4ab7..9ca4984a8b87 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -5242,7 +5242,7 @@ void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
if (VALID_PAGE(mmu->prev_root.hpa))
mmu->invlpg(vcpu, gva, mmu->prev_root.hpa);
- kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
+ kvm_x86_ops->tlb_flush_gva(vcpu, gva);
++vcpu->stat.invlpg;
}
EXPORT_SYMBOL_GPL(kvm_mmu_invlpg);
@@ -5250,18 +5250,22 @@ EXPORT_SYMBOL_GPL(kvm_mmu_invlpg);
void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid)
{
struct kvm_mmu *mmu = &vcpu->arch.mmu;
+ bool tlb_flush = false;
if (pcid == kvm_get_active_pcid(vcpu)) {
mmu->invlpg(vcpu, gva, mmu->root_hpa);
- kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
+ tlb_flush = true;
}
if (VALID_PAGE(mmu->prev_root.hpa) &&
pcid == kvm_get_pcid(vcpu, mmu->prev_root.cr3)) {
mmu->invlpg(vcpu, gva, mmu->prev_root.hpa);
- kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
+ tlb_flush = true;
}
+ if (tlb_flush)
+ kvm_x86_ops->tlb_flush_gva(vcpu, gva);
+
++vcpu->stat.invlpg;
/*
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index be9931cad409..73e27a98456f 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -5434,6 +5434,13 @@ static void svm_flush_tlb(struct kvm_vcpu *vcpu, bool invalidate_gpa)
svm->asid_generation--;
}
+static void svm_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t gva)
+{
+ struct vcpu_svm *svm = to_svm(vcpu);
+
+ invlpga(gva, svm->vmcb->control.asid);
+}
+
static void svm_prepare_guest_switch(struct kvm_vcpu *vcpu)
{
}
@@ -7086,6 +7093,7 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
.set_rflags = svm_set_rflags,
.tlb_flush = svm_flush_tlb,
+ .tlb_flush_gva = svm_flush_tlb_gva,
.run = svm_vcpu_run,
.handle_exit = handle_exit,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 7188dbdbedb2..1408cd4faf1f 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -1955,6 +1955,19 @@ static void loaded_vmcs_clear(struct loaded_vmcs *loaded_vmcs)
__loaded_vmcs_clear, loaded_vmcs, 1);
}
+static inline bool vpid_sync_vcpu_addr(int vpid, gva_t addr)
+{
+ if (vpid == 0)
+ return true;
+
+ if (cpu_has_vmx_invvpid_individual_addr()) {
+ __invvpid(VMX_VPID_EXTENT_INDIVIDUAL_ADDR, vpid, addr);
+ return true;
+ }
+
+ return false;
+}
+
static inline void vpid_sync_vcpu_single(int vpid)
{
if (vpid == 0)
@@ -4768,6 +4781,28 @@ static void vmx_flush_tlb(struct kvm_vcpu *vcpu, bool invalidate_gpa)
__vmx_flush_tlb(vcpu, to_vmx(vcpu)->vpid, invalidate_gpa);
}
+static void vmx_flush_tlb_gva(struct kvm_vcpu *vcpu, gva_t addr)
+{
+ int vpid = to_vmx(vcpu)->vpid;
+
+ /*
+ * We can only get a non-canonical address here if called through
+ * kvm_mmu_invlpg(). So it is ok to ignore it because an INVLPG on a
+ * non-canonical address is a NOP according to the Intel SDM.
+ */
+ if (is_noncanonical_address(addr, vcpu))
+ return;
+
+ if (!vpid_sync_vcpu_addr(vpid, addr))
+ vpid_sync_context(vpid);
+
+ /*
+ * If VPIDs are not supported or enabled, then the above is a no-op.
+ * But we don't really need a TLB flush in that case anyway, because
+ * each VM entry/exit includes an implicit flush when VPID is 0.
+ */
+}
+
static void vmx_decache_cr0_guest_bits(struct kvm_vcpu *vcpu)
{
ulong cr0_guest_owned_bits = vcpu->arch.cr0_guest_owned_bits;
@@ -13058,6 +13093,7 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = {
.set_rflags = vmx_set_rflags,
.tlb_flush = vmx_flush_tlb,
+ .tlb_flush_gva = vmx_flush_tlb_gva,
.run = vmx_vcpu_run,
.handle_exit = vmx_handle_exit,
--
2.18.0.399.gad0ab374a1-goog
