KVM: arm64: Reset VM feature ID regs from kvm_reset_sys_regs()

A subsequent change to KVM will expand the range of feature ID registers
that get special treatment at reset. Fold the existing ones back in to
kvm_reset_sys_regs() to avoid the need for an additional table walk.

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240502233529.1958459-3-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 51a6f91607e5bd1053b7b553a83cc20aa8d28f89..bb09ce4bce4594a793961e73e17623d4fd3777f3 100644 (file)
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -3510,26 +3510,16 @@ void kvm_sys_regs_create_debugfs(struct kvm *kvm)
                            &idregs_debug_fops);
 }
 
-static void kvm_reset_id_regs(struct kvm_vcpu *vcpu)
+static void reset_vm_ftr_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *reg)
 {
-       const struct sys_reg_desc *idreg = first_idreg;
-       u32 id = reg_to_encoding(idreg);
+       u32 id = reg_to_encoding(reg);
        struct kvm *kvm = vcpu->kvm;
 
        if (test_bit(KVM_ARCH_FLAG_ID_REGS_INITIALIZED, &kvm->arch.flags))
                return;
 
        lockdep_assert_held(&kvm->arch.config_lock);
-
-       /* Initialize all idregs */
-       while (is_vm_ftr_id_reg(id)) {
-               IDREG(kvm, id) = idreg->reset(vcpu, idreg);
-
-               idreg++;
-               id = reg_to_encoding(idreg);
-       }
-
-       set_bit(KVM_ARCH_FLAG_ID_REGS_INITIALIZED, &kvm->arch.flags);
+       IDREG(kvm, id) = reg->reset(vcpu, reg);
 }
 
 /**
@@ -3541,19 +3531,22 @@ static void kvm_reset_id_regs(struct kvm_vcpu *vcpu)
  */
 void kvm_reset_sys_regs(struct kvm_vcpu *vcpu)
 {
+       struct kvm *kvm = vcpu->kvm;
        unsigned long i;
 
-       kvm_reset_id_regs(vcpu);
-
        for (i = 0; i < ARRAY_SIZE(sys_reg_descs); i++) {
                const struct sys_reg_desc *r = &sys_reg_descs[i];
 
-               if (is_vm_ftr_id_reg(reg_to_encoding(r)))
+               if (!r->reset)
                        continue;
 
-               if (r->reset)
+               if (is_vm_ftr_id_reg(reg_to_encoding(r)))
+                       reset_vm_ftr_id_reg(vcpu, r);
+               else
                        r->reset(vcpu, r);
        }
+
+       set_bit(KVM_ARCH_FLAG_ID_REGS_INITIALIZED, &kvm->arch.flags);
 }
 
 /**