4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Vitaly Kuznetsov <vkuzn...@redhat.com>

commit 6b1971c694975e49af302229202c0043568b1791 upstream.

SDM says MSR_IA32_VMX_PROCBASED_CTLS2 is only available "If
(CPUID.01H:ECX.[5] && IA32_VMX_PROCBASED_CTLS[63])". It was found that
some old cpus (namely "Intel(R) Core(TM)2 CPU 6600 @ 2.40GHz (family: 0x6,
model: 0xf, stepping: 0x6") don't have it. Add the missing check.

Reported-by: Zdenek Kaspar <zkaspa...@gmail.com>
Tested-by: Zdenek Kaspar <zkaspa...@gmail.com>
Signed-off-by: Vitaly Kuznetsov <vkuzn...@redhat.com>
Reviewed-by: Jim Mattson <jmatt...@google.com>
Cc: sta...@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 arch/x86/kvm/vmx.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -3601,9 +3601,11 @@ static void nested_vmx_setup_ctls_msrs(s
         * secondary cpu-based controls.  Do not include those that
         * depend on CPUID bits, they are added later by vmx_cpuid_update.
         */
-       rdmsr(MSR_IA32_VMX_PROCBASED_CTLS2,
-               msrs->secondary_ctls_low,
-               msrs->secondary_ctls_high);
+       if (msrs->procbased_ctls_high & CPU_BASED_ACTIVATE_SECONDARY_CONTROLS)
+               rdmsr(MSR_IA32_VMX_PROCBASED_CTLS2,
+                     msrs->secondary_ctls_low,
+                     msrs->secondary_ctls_high);
+
        msrs->secondary_ctls_low = 0;
        msrs->secondary_ctls_high &=
                SECONDARY_EXEC_DESC |


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