Re: [PATCH mm v4 28/39] kasan, page_alloc: allow skipping unpoisoning for HW_TAGS

From: Marco Elver
Date: Tue Dec 21 2021 - 07:14:44 EST


On Mon, Dec 20, 2021 at 11:02PM +0100, andrey.konovalov@xxxxxxxxx wrote:
[...]
> +static inline bool should_skip_kasan_unpoison(gfp_t flags, bool init_tags)
> +{
> + /* Don't skip if a software KASAN mode is enabled. */
> + if (IS_ENABLED(CONFIG_KASAN_GENERIC) ||
> + IS_ENABLED(CONFIG_KASAN_SW_TAGS))
> + return false;
> +
> + /* Skip, if hardware tag-based KASAN is not enabled. */
> + if (!kasan_hw_tags_enabled())
> + return true;

Same question here: why is IS_ENABLED(CONFIG_KASAN_{GENERIC,SW_TAGS})
check required if kasan_hw_tags_enabled() is always false if one of
those is configured?