Re: [qemu-s390x] [Qemu-devel] [PATCH v2 26/28] s390x/tcg: MVST: Fault-safe handling

[Richard Henderson]

On 9/6/19 3:57 AM, David Hildenbrand wrote:
> +    /*
> +     * Our access should not exceed single pages, as we must not report 
> access
> +     * exceptions exceeding the actually copied range (which we don't know at
> +     * this point). We might over-indicate watchpoints within the pages
> +     * (if we ever care, we have to limit processing to a single byte).
> +     */
> +    srca = access_prepare(env, s, len, MMU_DATA_LOAD, ra);
> +    desta = access_prepare(env, d, len, MMU_DATA_STORE, ra);
> +    for (i = 0; i < len; i++) {
> +        const uint8_t v = access_get_byte(env, &srca, i, ra);
> +
> +        access_set_byte(env, &desta, i, v, ra);
>          if (v == c) {
> -            set_address_zero(env, r1, d + len);
> +            set_address_zero(env, r1, d + i);
>              return 1;
>          }

Worth using memchr + memmove w/ nondestructive overlap?

That said,
Reviewed-by: Richard Henderson <address@hidden>

r~