Re: [PATCH] selftests: KVM: aarch64: Let hypercalls use UAPI *_BIT_COUNT

From: Paolo Bonzini
Date: Thu May 05 2022 - 09:33:34 EST


On 5/5/22 14:04, Marc Zyngier wrote:
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index e523bb6eac67..3cde9f958eee 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -342,6 +342,10 @@ struct kvm_arm_copy_mte_tags {
enum {
KVM_REG_ARM_STD_BIT_TRNG_V1_0 = 0,
+ /*
+ * KVM_REG_ARM_STD_BMAP_BIT_COUNT will vary as new services
+ * are added, and is explicitely not part of the ABI.
+ */
KVM_REG_ARM_STD_BMAP_BIT_COUNT,
};

That seems like a bad idea. Perhaps you can wrap it in #ifdef __KERNEL_OR_SELFTESTS__? I can't find any prior art.

Paolo