From: Joerg Roedel <[EMAIL PROTECTED]> This patch introduces a guest TLB flush on every NPF exit in KVM. This fixes random segfaults and #UD exceptions in the guest seen under some workloads (e.g. long running compile workloads or tbench). A kernbench run with and without that fix showed that it has a slowdown lower than 0.5%
Cc: [EMAIL PROTECTED] Signed-off-by: Joerg Roedel <[EMAIL PROTECTED]> Signed-off-by: Alexander Graf <[EMAIL PROTECTED]> --- arch/x86/kvm/svm.c | 10 +++++++++- 1 files changed, 9 insertions(+), 1 deletions(-) diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 2d5aed4..980f140 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -59,6 +59,7 @@ static int npt = 1; module_param(npt, int, S_IRUGO); static void kvm_reput_irq(struct vcpu_svm *svm); +static void svm_flush_tlb(struct kvm_vcpu *vcpu); static inline struct vcpu_svm *to_svm(struct kvm_vcpu *vcpu) { @@ -1004,10 +1005,17 @@ static int pf_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run) KVMTRACE_3D(PAGE_FAULT, &svm->vcpu, error_code, (u32)fault_address, (u32)(fault_address >> 32), handler); - else + else { KVMTRACE_3D(TDP_FAULT, &svm->vcpu, error_code, (u32)fault_address, (u32)(fault_address >> 32), handler); + /* + * FIXME: Tis shouldn't be necessary here, but there is a flush + * missing in the MMU code. Until we find this bug, flush the + * complete TLB here on an NPF + */ + svm_flush_tlb(&svm->vcpu); + } if (event_injection) kvm_mmu_unprotect_page_virt(&svm->vcpu, fault_address); -- 1.5.3.7 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html