On Fri, Oct 30, 2020 at 4:48 PM Andrey Konovalov <andreyknvl@xxxxxxxxxx> wrote: > > On Wed, Oct 28, 2020 at 12:08 PM Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote: > > > > On Thu, Oct 22, 2020 at 3:19 PM Andrey Konovalov <andreyknvl@xxxxxxxxxx> wrote: > > > > > > Using random_tag() currently results in a function call. Move its > > > definition to mm/kasan/kasan.h and turn it into a static inline function > > > for hardware tag-based mode to avoid uneeded function call. > > > > > > Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> > > > Link: https://linux-review.googlesource.com/id/Iac5b2faf9a912900e16cca6834d621f5d4abf427 > > > --- > > > mm/kasan/hw_tags.c | 5 ----- > > > mm/kasan/kasan.h | 37 ++++++++++++++++++++----------------- > > > 2 files changed, 20 insertions(+), 22 deletions(-) > > > > > > diff --git a/mm/kasan/hw_tags.c b/mm/kasan/hw_tags.c > > > index c3a0e83b5e7a..4c24bfcfeff9 100644 > > > --- a/mm/kasan/hw_tags.c > > > +++ b/mm/kasan/hw_tags.c > > > @@ -36,11 +36,6 @@ void kasan_unpoison_memory(const void *address, size_t size) > > > round_up(size, KASAN_GRANULE_SIZE), get_tag(address)); > > > } > > > > > > -u8 random_tag(void) > > > -{ > > > - return get_random_tag(); > > > -} > > > - > > > bool check_invalid_free(void *addr) > > > { > > > u8 ptr_tag = get_tag(addr); > > > diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h > > > index 0ccbb3c4c519..94ba15c2f860 100644 > > > --- a/mm/kasan/kasan.h > > > +++ b/mm/kasan/kasan.h > > > @@ -188,6 +188,12 @@ static inline bool addr_has_metadata(const void *addr) > > > > > > #endif /* CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS */ > > > > > > +#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) > > > +void print_tags(u8 addr_tag, const void *addr); > > > +#else > > > +static inline void print_tags(u8 addr_tag, const void *addr) { } > > > +#endif > > > + > > > bool check_invalid_free(void *addr); > > > > > > void *find_first_bad_addr(void *addr, size_t size); > > > @@ -223,23 +229,6 @@ static inline void quarantine_reduce(void) { } > > > static inline void quarantine_remove_cache(struct kmem_cache *cache) { } > > > #endif > > > > > > -#if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS) > > > - > > > -void print_tags(u8 addr_tag, const void *addr); > > > - > > > -u8 random_tag(void); > > > - > > > -#else > > > - > > > -static inline void print_tags(u8 addr_tag, const void *addr) { } > > > - > > > -static inline u8 random_tag(void) > > > -{ > > > - return 0; > > > -} > > > - > > > -#endif > > > - > > > #ifndef arch_kasan_set_tag > > > static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) > > > { > > > @@ -273,6 +262,20 @@ static inline const void *arch_kasan_set_tag(const void *addr, u8 tag) > > > #define get_mem_tag(addr) arch_get_mem_tag(addr) > > > #define set_mem_tag_range(addr, size, tag) arch_set_mem_tag_range((addr), (size), (tag)) > > > > > > +#ifdef CONFIG_KASAN_SW_TAGS > > > +u8 random_tag(void); > > > +#elif defined(CONFIG_KASAN_HW_TAGS) > > > +static inline u8 random_tag(void) > > > +{ > > > + return get_random_tag(); > > > > What's the difference between random_tag() and get_random_tag()? Do we > > need both? > > Not really. Will simplify this in the next version and give cleaner names. Actually I think I'll keep both for the next version, but rename get_random_tag() into hw_get_random_tag() along with other hw-specific calls. The idea is to have hw_*() calls for things that are implemented by the hardware for HW_TAGS, and then define random_tag() based on that for HW_TAGS and based on a software implementation for SW_TAGS.
