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    Subject[PATCH 5.10 259/289] KVM: VMX: Do not advertise RDPID if ENABLE_RDTSCP control is unsupported
    Date
    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(-)

    --- 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);

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