On 10/18/2017 12:02 PM, Cornelia Huck wrote:
> On Wed, 18 Oct 2017 12:00:05 +0200
> Thomas Huth <th...@redhat.com> wrote:
>
>> On 17.10.2017 16:04, Halil Pasic wrote:
>>> Simplify the error handling of the MSCH. Let the code detecting the
>>> condition tell (in a less ambiguous way) how it's to be handled. No
>>> changes in behavior.
>>
>> ok, so you claim no changes in behavior ...
>>
>>> Signed-off-by: Halil Pasic <pa...@linux.vnet.ibm.com>
>>> ---
>>> hw/s390x/css.c | 18 +++++-------------
>>> include/hw/s390x/css.h | 2 +-
>>> target/s390x/ioinst.c | 23 ++++-------------------
>>> 3 files changed, 10 insertions(+), 33 deletions(-)
>>>
>>> diff --git a/hw/s390x/css.c b/hw/s390x/css.c
>>> index b9e0329825..30fc236946 100644
>>> --- a/hw/s390x/css.c
>>> +++ b/hw/s390x/css.c
>>> @@ -1347,28 +1347,24 @@ static void copy_schib_from_guest(SCHIB *dest,
>>> const SCHIB *src)
>>> }
>>> }
>>>
>>> -int css_do_msch(SubchDev *sch, const SCHIB *orig_schib)
>>> +IOInstEnding css_do_msch(SubchDev *sch, const SCHIB *orig_schib)
>>> {
>>> SCSW *s = &sch->curr_status.scsw;
>>> PMCW *p = &sch->curr_status.pmcw;
>>> uint16_t oldflags;
>>> - int ret;
>>> SCHIB schib;
>>>
>>> if (!(sch->curr_status.pmcw.flags & PMCW_FLAGS_MASK_DNV)) {
>>> - ret = 0;
>>> - goto out;
>>> + return IOINST_CC_EXPECTED;
>>> }
>>>
>>> if (s->ctrl & SCSW_STCTL_STATUS_PEND) {
>>> - ret = -EINPROGRESS;
>>> - goto out;
>>> + return IOINST_CC_STATUS_PRESENT;
>>> }
>>>
>>> if (s->ctrl &
>>> (SCSW_FCTL_START_FUNC|SCSW_FCTL_HALT_FUNC|SCSW_FCTL_CLEAR_FUNC)) {
>>> - ret = -EBUSY;
>>> - goto out;
>>> + return IOINST_CC_STATUS_PRESENT;
>>> }
>>
>> ... but here you change -EBUSY (which got mapped to CC=2) to
>> CC_STATUS_PRESENT which means CC=1. So that's a change in behavior. i.e.
>> this is either a bug, or you should update the patch description with a
>> justification for this change in behavior.
>
> Indeed, that's a bug. We still want cc 2.
>
Agree, it is a bug. It was OK in v1 but was already buggy in
v2.
Conny can you fix this up as well please?
Thanks in advance!
Halil
