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| author | Joerg Roedel <joerg.roedel@amd.com> | 2008-08-27 14:18:43 +0200 |
|---|---|---|
| committer | Avi Kivity <avi@qumranet.com> | 2008-09-11 10:31:53 +0200 |
| commit | 44874f84918e37b64bec6df1587e5fe2fdf6ab62 (patch) | |
| tree | 8fc95bb2358322ddd9307d231849d7c0a064b001 /arch | |
| parent | Linux 2.6.27-rc6 (diff) | |
| download | linux-44874f84918e37b64bec6df1587e5fe2fdf6ab62.tar.xz linux-44874f84918e37b64bec6df1587e5fe2fdf6ab62.zip | |
KVM: SVM: fix random segfaults with NPT enabled
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: stable@kernel.org
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/svm.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index e2ee264740c7..d1106cddab0d 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -62,6 +62,7 @@ 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) { @@ -1027,6 +1028,13 @@ static int pf_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run) 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 + */ + if (npt_enabled) + svm_flush_tlb(&svm->vcpu); if (event_injection) kvm_mmu_unprotect_page_virt(&svm->vcpu, fault_address); |