KVM: SVM: Move global "avic" variable to avic.c

Move "avic" to avic.c so that it's colocated with the other AVIC specific
globals and module params, and so that avic_hardware_setup() is a bit more
self-contained, e.g. similar to sev_hardware_setup().

Deliberately set enable_apicv in svm.c as it's already globally visible
(defined by kvm.ko, not by kvm-amd.ko), and to clearly capture the
dependency on enable_apicv being initialized (svm_hardware_setup() clears
several AVIC-specific hooks when enable_apicv is disabled).

Alternatively, clearing of the hooks (and enable_ipiv) could be moved to
avic_hardware_setup(), but that's not obviously better, e.g. it's helpful
to isolate the setting of enable_apicv when reading code from the generic
x86 side of the world.

No functional change intended.

Acked-by: Naveen N Rao (AMD) <naveen@kernel.org>
Tested-by: Naveen N Rao (AMD) <naveen@kernel.org>
Link: https://lore.kernel.org/r/20250919215934.1590410-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 35dde7d89f5657fe0d5505dbbf4b828be86011c1..ec214062d136162426f2a380c51835e19711ebf1 100644 (file)
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -64,6 +64,14 @@
 
 static_assert(__AVIC_GATAG(AVIC_VM_ID_MASK, AVIC_VCPU_IDX_MASK) == -1u);
 
+/*
+ * enable / disable AVIC.  Because the defaults differ for APICv
+ * support between VMX and SVM we cannot use module_param_named.
+ */
+static bool avic;
+module_param(avic, bool, 0444);
+module_param(enable_ipiv, bool, 0444);
+
 static bool force_avic;
 module_param_unsafe(force_avic, bool, 0444);
 
@@ -1141,15 +1149,9 @@ void avic_vcpu_unblocking(struct kvm_vcpu *vcpu)
        avic_vcpu_load(vcpu, vcpu->cpu);
 }
 
-/*
- * Note:
- * - The module param avic enable both xAPIC and x2APIC mode.
- * - Hypervisor can support both xAVIC and x2AVIC in the same guest.
- * - The mode can be switched at run-time.
- */
-bool __init avic_hardware_setup(void)
+static bool __init avic_want_avic_enabled(void)
 {
-       if (!npt_enabled)
+       if (!avic || !npt_enabled)
                return false;
 
        /* AVIC is a prerequisite for x2AVIC. */
@@ -1173,6 +1175,21 @@ bool __init avic_hardware_setup(void)
        if (!boot_cpu_has(X86_FEATURE_AVIC))
                pr_warn("AVIC unsupported in CPUID but force enabled, your system might crash and burn\n");
 
+       return true;
+}
+
+/*
+ * Note:
+ * - The module param avic enable both xAPIC and x2APIC mode.
+ * - Hypervisor can support both xAVIC and x2AVIC in the same guest.
+ * - The mode can be switched at run-time.
+ */
+bool __init avic_hardware_setup(void)
+{
+       avic = avic_want_avic_enabled();
+       if (!avic)
+               return false;
+
        pr_info("AVIC enabled\n");
 
        /* AVIC is a prerequisite for x2AVIC. */

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 3fd2f4097a3b1d36c8295decdc6bcf930ce4105f..748881a3dedb64b4105ef58a55156f58e789a31c 100644 (file)
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -158,14 +158,6 @@ module_param(lbrv, int, 0444);
 static int tsc_scaling = true;
 module_param(tsc_scaling, int, 0444);
 
-/*
- * enable / disable AVIC.  Because the defaults differ for APICv
- * support between VMX and SVM we cannot use module_param_named.
- */
-static bool avic;
-module_param(avic, bool, 0444);
-module_param(enable_ipiv, bool, 0444);
-
 module_param(enable_device_posted_irqs, bool, 0444);
 
 bool __read_mostly dump_invalid_vmcb;
@@ -5330,8 +5322,7 @@ static __init int svm_hardware_setup(void)
                        goto err;
        }
 
-       enable_apicv = avic = avic && avic_hardware_setup();
-
+       enable_apicv = avic_hardware_setup();
        if (!enable_apicv) {
                enable_ipiv = false;
                svm_x86_ops.vcpu_blocking = NULL;