On Mon, Mar 08, 2021 at 04:55:14PM +0100, Andrey Konovalov wrote: > @@ -68,10 +69,16 @@ static inline void mte_set_mem_tag_range(void *addr, size_t size, u8 tag) > * 'asm volatile' is required to prevent the compiler to move > * the statement outside of the loop. > */ > - asm volatile(__MTE_PREAMBLE "stg %0, [%0]" > - : > - : "r" (curr) > - : "memory"); > + if (init) > + asm volatile(__MTE_PREAMBLE "stzg %0, [%0]" > + : > + : "r" (curr) > + : "memory"); > + else > + asm volatile(__MTE_PREAMBLE "stg %0, [%0]" > + : > + : "r" (curr) > + : "memory"); > > curr += MTE_GRANULE_SIZE; > } while (curr != end); Is 'init' always a built-in constant here? If not, checking it once outside the loop may be better (or check the code generation, maybe the compiler is smart enough). -- Catalin