Commit ef697a71 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

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 518c8aee ("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: default avatar <jmontleo@redhat.com>
Tested-by: default avatar <jmontleo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 99b83ac8
Reviewed-by: default avatarDavid Matlack <dmatlack@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent f6870ee9

arch/x86/kvm/vmx.c

+13 −1
Original line number Diff line number Diff line
@@ -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;

	}

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