Re: [qemu-s390x] [Qemu-devel] [PATCH v1 2/2] s390x/tcg: Store only the necessary amount of doublewords for STFLE

[Richard Henderson]

On 5/31/19 9:56 AM, David Hildenbrand wrote:
> @@ -678,7 +678,7 @@ uint32_t HELPER(stfle)(CPUS390XState *env, uint64_t addr)
>  
>      prepare_stfl();
>      max_bytes = ROUND_UP(used_stfl_bytes, 8);
> -    for (i = 0; i < count_bytes; ++i) {
> +    for (i = 0; i < MIN(count_bytes, max_bytes); ++i) {

Before the loop, please put something like

    /*
     * The PoP says that doublewords beyond the highest-numbered
     * facility bit may or may not be stored.  However, existing
     * hardware appears to not store the words, and existing
     * software appears to depend on that.
     */

with that,
Reviewed-by: Richard Henderson <address@hidden>


r~