From ef697a712a6165aea7779c295604b099e8bfae2e Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Fri, 18 Mar 2016 16:58:38 +0100 Subject: [PATCH] KVM: VMX: fix nested vpid for old KVM guests Old KVM guests invoke single-context invvpid without actually checking whether it is supported. This was fixed by commit 518c8ae ("KVM: VMX: Make sure single type invvpid is supported before issuing invvpid instruction", 2010-08-01) and the patch after, but pre-2.6.36 kernels lack it including RHEL 6. Reported-by: jmontleo@redhat.com Tested-by: jmontleo@redhat.com Cc: stable@vger.kernel.org Fixes: 99b83ac893b84ed1a62ad6d1f2b6cc32026b9e85 Reviewed-by: David Matlack Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 0ce009c..1612300 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2712,8 +2712,15 @@ static void nested_vmx_setup_ctls_msrs(struct vcpu_vmx *vmx) } else vmx->nested.nested_vmx_ept_caps = 0; + /* + * Old versions of KVM use the single-context version without + * checking for support, so declare that it is supported even + * though it is treated as global context. The alternative is + * not failing the single-context invvpid, and it is worse. + */ if (enable_vpid) vmx->nested.nested_vmx_vpid_caps = VMX_VPID_INVVPID_BIT | + VMX_VPID_EXTENT_SINGLE_CONTEXT_BIT | VMX_VPID_EXTENT_GLOBAL_CONTEXT_BIT; else vmx->nested.nested_vmx_vpid_caps = 0; @@ -7475,12 +7482,17 @@ static int handle_invvpid(struct kvm_vcpu *vcpu) } switch (type) { + case VMX_VPID_EXTENT_SINGLE_CONTEXT: + /* + * Old versions of KVM use the single-context version so we + * have to support it; just treat it the same as all-context. + */ case VMX_VPID_EXTENT_ALL_CONTEXT: __vmx_flush_tlb(vcpu, to_vmx(vcpu)->nested.vpid02); nested_vmx_succeed(vcpu); break; default: - /* Trap single context invalidation invvpid calls */ + /* Trap individual address invalidation invvpid calls */ BUG_ON(1); break; } -- 2.7.4