KVM: x86: Move some EFER bits enablement to common code

Move EFER bits enablement that only depend on CPU support to common
code, as there is no reason to do it in vendor code. Leave EFER.SVME and
EFER.LMSLE enablement in SVM code as they depend on vendor module
parameters.

Having the enablement in common code ensures that if a vendor starts
supporting an existing feature, KVM doesn't end up advertising to
userspace but not allowing the EFER bit to be set.

No functional change intended.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Yosry Ahmed <yosry@kernel.org>
Link: https://patch.msgid.link/20260307011619.2324234-2-yosry@kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 936f7652d1e49f70634d71928e468f523e2e3882..424ed50e6bfa742488f7d4542d3f3af871f96310 100644 (file)
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -5405,14 +5405,10 @@ static __init int svm_hardware_setup(void)
                pr_err_ratelimited("NX (Execute Disable) not supported\n");
                return -EOPNOTSUPP;
        }
-       kvm_enable_efer_bits(EFER_NX);
 
        kvm_caps.supported_xcr0 &= ~(XFEATURE_MASK_BNDREGS |
                                     XFEATURE_MASK_BNDCSR);
 
-       if (boot_cpu_has(X86_FEATURE_FXSR_OPT))
-               kvm_enable_efer_bits(EFER_FFXSR);
-
        if (tsc_scaling) {
                if (!boot_cpu_has(X86_FEATURE_TSCRATEMSR)) {
                        tsc_scaling = false;
@@ -5426,9 +5422,6 @@ static __init int svm_hardware_setup(void)
 
        tsc_aux_uret_slot = kvm_add_user_return_msr(MSR_TSC_AUX);
 
-       if (boot_cpu_has(X86_FEATURE_AUTOIBRS))
-               kvm_enable_efer_bits(EFER_AUTOIBRS);
-
        /* Check for pause filtering support */
        if (!boot_cpu_has(X86_FEATURE_PAUSEFILTER)) {
                pause_filter_count = 0;

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 967b58a8ab9d0d47fb24def7b4ae70bfbe9d5ec0..bc28da49f2839c689d76b8982905c2d9740ba679 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -8694,10 +8694,6 @@ __init int vmx_hardware_setup(void)
 
        vmx_setup_user_return_msrs();
 
-
-       if (boot_cpu_has(X86_FEATURE_NX))
-               kvm_enable_efer_bits(EFER_NX);
-
        if (boot_cpu_has(X86_FEATURE_MPX)) {
                rdmsrq(MSR_IA32_BNDCFGS, host_bndcfgs);
                WARN_ONCE(host_bndcfgs, "BNDCFGS in host will be lost");

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index d5731499f4c2c89d3509a51f9e4d5c4a372c0b3e..7e8c1816cffd6bf9a3738cc29307607d6d3b1d2d 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9998,6 +9998,18 @@ void kvm_setup_xss_caps(void)
 }
 EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_setup_xss_caps);
 
+static void kvm_setup_efer_caps(void)
+{
+       if (boot_cpu_has(X86_FEATURE_NX))
+               kvm_enable_efer_bits(EFER_NX);
+
+       if (boot_cpu_has(X86_FEATURE_FXSR_OPT))
+               kvm_enable_efer_bits(EFER_FFXSR);
+
+       if (boot_cpu_has(X86_FEATURE_AUTOIBRS))
+               kvm_enable_efer_bits(EFER_AUTOIBRS);
+}
+
 static inline void kvm_ops_update(struct kvm_x86_init_ops *ops)
 {
        memcpy(&kvm_x86_ops, ops->runtime_ops, sizeof(kvm_x86_ops));
@@ -10134,6 +10146,8 @@ int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
        if (r != 0)
                goto out_mmu_exit;
 
+       kvm_setup_efer_caps();
+
        enable_device_posted_irqs &= enable_apicv &&
                                     irq_remapping_cap(IRQ_POSTING_CAP);