2 files changed, 21 insertions, 8 deletions
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 2071260a275b..e8bf08e09f78 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -2094,9 +2094,9 @@ static void unhandled_cp_access(struct kvm_vcpu *vcpu,
 		WARN_ON(1);
 	}
 
-	kvm_err("Unsupported guest CP%d access at: %08lx [%08lx]\n",
-		cp, *vcpu_pc(vcpu), *vcpu_cpsr(vcpu));
-	print_sys_reg_instr(params);
+	print_sys_reg_msg(params,
+			  "Unsupported guest CP%d access at: %08lx [%08lx]\n",
+			  cp, *vcpu_pc(vcpu), *vcpu_cpsr(vcpu));
 	kvm_inject_undefined(vcpu);
 }
 
@@ -2245,9 +2245,9 @@ static int emulate_sys_reg(struct kvm_vcpu *vcpu,
 	if (likely(r)) {
 		perform_access(vcpu, params, r);
 	} else {
-		kvm_err("Unsupported guest sys_reg access at: %lx [%08lx]\n",
-			*vcpu_pc(vcpu), *vcpu_cpsr(vcpu));
-		print_sys_reg_instr(params);
+		print_sys_reg_msg(params,
+				  "Unsupported guest sys_reg access at: %lx [%08lx]\n",
+				  *vcpu_pc(vcpu), *vcpu_cpsr(vcpu));
 		kvm_inject_undefined(vcpu);
 	}
 	return 1;
diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h
index 9bca0312d798..5a6fc30f5989 100644
--- a/arch/arm64/kvm/sys_regs.h
+++ b/arch/arm64/kvm/sys_regs.h
@@ -62,11 +62,24 @@ struct sys_reg_desc {
 #define REG_HIDDEN_USER		(1 << 0) /* hidden from userspace ioctls */
 #define REG_HIDDEN_GUEST	(1 << 1) /* hidden from guest */
 
-static inline void print_sys_reg_instr(const struct sys_reg_params *p)
+static __printf(2, 3)
+inline void print_sys_reg_msg(const struct sys_reg_params *p,
+				       char *fmt, ...)
 {
+	va_list va;
+
+	va_start(va, fmt);
 	/* Look, we even formatted it for you to paste into the table! */
-	kvm_pr_unimpl(" { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n",
+	kvm_pr_unimpl("%pV { Op0(%2u), Op1(%2u), CRn(%2u), CRm(%2u), Op2(%2u), func_%s },\n",
+		      &(struct va_format){ fmt, &va },
 		      p->Op0, p->Op1, p->CRn, p->CRm, p->Op2, p->is_write ? "write" : "read");
+	va_end(va);
+}
+
+static inline void print_sys_reg_instr(const struct sys_reg_params *p)
+{
+	/* GCC warns on an empty format string */
+	print_sys_reg_msg(p, "%s", "");
 }
 
 static inline bool ignore_write(struct kvm_vcpu *vcpu,