kvm: x86: Flush only affected TLB entries in kvm_mmu_invlpg*

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@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Junaid Shahid 2018-06-29 13:10:05 -07:00 committed by Paolo Bonzini
parent 956bf3531f
commit faff87588d
4 changed files with 55 additions and 3 deletions

View File

@ -985,6 +985,14 @@ 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);

View File

@ -5226,6 +5226,10 @@ void kvm_mmu_invlpg(struct kvm_vcpu *vcpu, gva_t gva)
{
struct kvm_mmu *mmu = &vcpu->arch.mmu;
/* INVLPG on a * non-canonical address is a NOP according to the SDM. */
if (is_noncanonical_address(gva, vcpu))
return;
mmu->invlpg(vcpu, gva, mmu->root_hpa);
/*
@ -5242,7 +5246,7 @@ 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 +5254,22 @@ 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;
/*

View File

@ -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,

View File

@ -1992,6 +1992,19 @@ 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)
@ -4833,6 +4846,20 @@ 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;
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;
@ -13603,6 +13630,7 @@ 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,