[PATCH 5.10 259/289] KVM: VMX: Do not advertise RDPID if ENABLE_RDTSCP control is unsupported

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Sean Christopherson <seanjc@xxxxxxxxxx>

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@xxxxxxxxxxxxxxx
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Message-Id: <20210504171734.1434054-2-seanjc@xxxxxxxxxx>
Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>
Reviewed-by: Reiji Watanabe <reijiw@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/x86/kvm/vmx/vmx.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7302,9 +7302,11 @@ 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);





[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux