KVM: arm64: Don't use empty structures as CPU reset state

Keeping empty structure as the vcpu state initializer is slightly
wasteful: we only want to set pstate, and zero everything else.
Just do that.

Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index 658f3a7..865c8aa 100644 (file)
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c
@@ -36,15 +36,11 @@ static u32 kvm_ipa_limit;
 /*
  * ARMv8 Reset Values
  */
-static const struct kvm_regs default_regs_reset = {
-       .regs.pstate = (PSR_MODE_EL1h | PSR_A_BIT | PSR_I_BIT |
-                       PSR_F_BIT | PSR_D_BIT),
-};
+#define VCPU_RESET_PSTATE_EL1  (PSR_MODE_EL1h | PSR_A_BIT | PSR_I_BIT | \
+                                PSR_F_BIT | PSR_D_BIT)
 
-static const struct kvm_regs default_regs_reset32 = {
-       .regs.pstate = (PSR_AA32_MODE_SVC | PSR_AA32_A_BIT |
-                       PSR_AA32_I_BIT | PSR_AA32_F_BIT),
-};
+#define VCPU_RESET_PSTATE_SVC  (PSR_AA32_MODE_SVC | PSR_AA32_A_BIT | \
+                                PSR_AA32_I_BIT | PSR_AA32_F_BIT)
 
 static bool cpu_has_32bit_el1(void)
 {
@@ -257,9 +253,9 @@ static int kvm_vcpu_enable_ptrauth(struct kvm_vcpu *vcpu)
  */
 int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
 {
-       const struct kvm_regs *cpu_reset;
        int ret = -EINVAL;
        bool loaded;
+       u32 pstate;
 
        /* Reset PMU outside of the non-preemptible section */
        kvm_pmu_vcpu_reset(vcpu);
@@ -290,16 +286,17 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
                if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) {
                        if (!cpu_has_32bit_el1())
                                goto out;
-                       cpu_reset = &default_regs_reset32;
+                       pstate = VCPU_RESET_PSTATE_SVC;
                } else {
-                       cpu_reset = &default_regs_reset;
+                       pstate = VCPU_RESET_PSTATE_EL1;
                }
 
                break;
        }
 
        /* Reset core registers */
-       memcpy(vcpu_gp_regs(vcpu), cpu_reset, sizeof(*cpu_reset));
+       memset(vcpu_gp_regs(vcpu), 0, sizeof(*vcpu_gp_regs(vcpu)));
+       vcpu_gp_regs(vcpu)->regs.pstate = pstate;
 
        /* Reset system registers */
        kvm_reset_sys_regs(vcpu);