diff mbox series

[5.12,333/363] KVM: VMX: Do not advertise RDPID if ENABLE_RDTSCP control is unsupported

Message ID 20210517140313.865730287@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg Kroah-Hartman May 17, 2021, 2:03 p.m. UTC 
From: Sean Christopherson <seanjc@google.com>

commit 8aec21c04caa2000f91cf8822ae0811e4b0c3971 upstream.

Clear KVM's RDPID capability if the ENABLE_RDTSCP secondary exec control is
unsupported.  Despite being enumerated in a separate CPUID flag, RDPID is
bundled under the same VMCS control as RDTSCP and will #UD in VMX non-root
if ENABLE_RDTSCP is not enabled.

Fixes: 41cd02c6f7f6 ("kvm: x86: Expose RDPID in KVM_GET_SUPPORTED_CPUID")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210504171734.1434054-2-seanjc@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 arch/x86/kvm/vmx/vmx.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
diff mbox series

Patch

--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7352,9 +7352,11 @@  static __init void vmx_set_cpu_caps(void
 	if (!cpu_has_vmx_xsaves())
 		kvm_cpu_cap_clear(X86_FEATURE_XSAVES);
 
-	/* CPUID 0x80000001 */
-	if (!cpu_has_vmx_rdtscp())
+	/* CPUID 0x80000001 and 0x7 (RDPID) */
+	if (!cpu_has_vmx_rdtscp()) {
 		kvm_cpu_cap_clear(X86_FEATURE_RDTSCP);
+		kvm_cpu_cap_clear(X86_FEATURE_RDPID);
+	}
 
 	if (cpu_has_vmx_waitpkg())
 		kvm_cpu_cap_check_and_set(X86_FEATURE_WAITPKG);