In response to https://lore.kernel.org/lkml/20201110162211.9207-6-yu-cheng.yu@xxxxxxxxx/. Hi Yu-cheng, This feature reminds me very much of ARCH_SUPPORTS_SHADOW_CALL_STACK/CC_HAVE_SHADOW_CALL_STACK implemented in https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5287569a790d2546a06db07e391bf84b8bd6cf51. Do you think it would be worthwhile to share the same config name between x86 and aarch64? (Though, it seems on x86 there will be a distinction between kernel mode and user mode configs, if I understand correctly?)