Re: [Qemu-devel] [PATCH v1] target/s390x: Add support for the TEST BLOCK instruction

[David Hildenbrand]

On 17.05.2017 18:05, Thomas Huth wrote:
> On 16.05.2017 21:06, Richard Henderson wrote:
>> On 05/16/2017 02:28 AM, Thomas Huth wrote:
>>> +void HELPER(testblock)(CPUS390XState *env, uint64_t addr)
>>> +{
>>> +    CPUState *cs = CPU(s390_env_get_cpu(env));
>>> +    int i;
>>> +
>>> +    addr = get_address(env, 0, 0, addr) & ~0xfffULL;
>>> +    for (i = 0; i < TARGET_PAGE_SIZE; i += 8) {
>>> +        stq_phys(cs->as, addr + i, 0);
>>> +    }
>>> +    env->cc_op = 0;
>>> +}
>>
>> This needs several changes: check that the physical page does indeed
>> exist, "low address protection", return the cc code.
> 
> Ok, ... but if we care about "low address protection", shouldn't we also
> add that to the other CPU instructions, too? (As far as I can see, it is
> not supported by the TCG code at all yet)

The same should be true for storage key checks, right? I think there are
a lot of such checks missing.


-- 

Thanks,

David