On 6/27/22 14:52, Claudio Imbrenda wrote:
> On Mon, 27 Jun 2022 14:43:56 +0200
> Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx> wrote:
>
>> According to the architecture, SET PREFIX must try to access the new
>> prefix area and recognize an addressing exception if the area is not
>> accessible.
>> Test that the exception occurs when we try to set a prefix higher
>> than the available memory.
>>
>> Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>
>> ---
>> s390x/intercept.c | 14 ++++++++++++++
>> 1 file changed, 14 insertions(+)
>>
>> diff --git a/s390x/intercept.c b/s390x/intercept.c
>> index 86e57e11..0b90e588 100644
>> --- a/s390x/intercept.c
>> +++ b/s390x/intercept.c
>> @@ -74,6 +74,20 @@ static void test_spx(void)
>> expect_pgm_int();
>> asm volatile(" spx 0(%0) " : : "r"(-8L));
>> check_pgm_int_code(PGM_INT_CODE_ADDRESSING);
>> +
>> + new_prefix = get_ram_size() & 0x7fffe000;
>> + if (get_ram_size() - new_prefix < 2 * PAGE_SIZE) {
>> + expect_pgm_int();
>> + asm volatile("spx %0 " : : "Q"(new_prefix));
>> + check_pgm_int_code(PGM_INT_CODE_ADDRESSING);
>> +
>> + /*
>> + * Cannot test inaccessibility of the second page the same way.
>> + * If we try to use the last page as first half of the prefix
>> + * area and our ram size is a multiple of 8k, after SPX aligns
>> + * the address to 8k we have a completely accessible area.
>> + */
>> + }
>
> please add something like:
>
> else {
> report_skip("Inaccessible prefix");
> }
>
Yeah, good idea.
Is there any low effort way of generating an invalid prefix other than > ram_size ?
That might then allow for testing the second page also.
>> }
>>
>> /* Test the STORE CPU ADDRESS instruction */
>>
>> base-commit: 110c69492b53f0070e1bbce986fb635e72a423b4
>
