Re: [PATCH v1] s390x/ioinst: Fix wrong MSCH alignment check on little endian

[Cornelia Huck]

On Fri, Aug 06 2021, David Hildenbrand <david@redhat.com> wrote:

> On 06.08.21 16:17, Philippe Mathieu-Daudé wrote:
>> On 8/6/21 1:30 PM, David Hildenbrand wrote:
>>> On 06.08.21 13:19, Cornelia Huck wrote:
>>>> On Thu, Aug 05 2021, David Hildenbrand <david@redhat.com> wrote:
>>>>
>>>>> schib->pmcw.chars is 32bit, not 16bit. This fixes the kvm-unit-tests
>>>>> "css" test, which fails with:
>>>>>
>>>>>     FAIL: Channel Subsystem: measurement block format1: Unaligned MB
>>>>> origin:
>>>>>     Program interrupt: expected(21) == received(0)
>>>>>
>>>>> Because we end up not injecting an operand program exception.
>>>>>
>>>>> Fixes: a54b8ac340c2 ("css: SCHIB measurement block origin must be
>>>>> aligned")
>>>>> Cc: Halil Pasic <pasic@linux.ibm.com>
>>>>> Cc: Cornelia Huck <cohuck@redhat.com>
>>>>> Cc: Christian Borntraeger <borntraeger@de.ibm.com>
>>>>> Cc: Richard Henderson <richard.henderson@linaro.org>
>>>>> Cc: Thomas Huth <thuth@redhat.com>
>>>>> Cc: Pierre Morel <pmorel@linux.ibm.com>
>>>>> Cc: qemu-s390x@nongnu.org
>>>>> Signed-off-by: David Hildenbrand <david@redhat.com>
>>>>> ---
>>>>>    target/s390x/ioinst.c | 2 +-
>>>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> Same question here: still -rc worthy, or not?
>>>>
>>>
>>> It's been broken forever, this can also wait I guess.
>> 
>> But the commit referenced is recent:
>> 
>> commit a54b8ac340c20531daa89929c5ce7fed89fa401d
>> Date:   Fri Feb 19 14:39:33 2021 +0100
>> 
>>      css: SCHIB measurement block origin must be aligned
>> 
>
> Well, okay yes :) I don't think it's very urgent though.

I think I agree. Before the referenced commit, we did not do any
alignment checks at all, now we still let some unaligned blocks
pass. I don't think I've seen any issues before, the problem has only
been uncovered by the kvm unit test. So fix-worthy, but probably not
late-rc-worthy.