[RFC PATCH v3 15/29] KVM: arm64: Make ID registers without id_reg_info writable

[Reiji Watanabe]

Make ID registers that don't have id_reg_info writable.

Signed-off-by: Reiji Watanabe <reijiw at google.com>
---
 arch/arm64/kvm/sys_regs.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 659ec880d527..35e458cc1e1d 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1886,16 +1886,12 @@ static int __set_id_reg(struct kvm_vcpu *vcpu,
 	if (err)
 		return err;
 
-	/* Don't allow to change the reg unless the reg has id_reg_info */
-	if (val != read_id_reg(vcpu, rd, raz) && !GET_ID_REG_INFO(encoding))
+	/* Don't allow to change the reg after the first KVM_RUN. */
+	if ((val != read_id_reg(vcpu, rd, raz)) && vcpu->arch.has_run_once)
 		return -EINVAL;
 
 	if (raz)
-		return 0;
-
-	/* Don't allow to change the reg after the first KVM_RUN. */
-	if (vcpu->arch.has_run_once)
-		return -EINVAL;
+		return (val == 0) ? 0 : -EINVAL;
 
 	err = validate_id_reg(vcpu, rd, val);
 	if (err)
-- 
2.34.0.rc1.387.gb447b232ab-goog