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| author | Halil Pasic <pasic@linux.vnet.ibm.com> | 2017-09-08 17:24:43 +0200 |
|---|---|---|
| committer | Cornelia Huck <cohuck@redhat.com> | 2017-09-19 18:21:33 +0200 |
| commit | 248b920df95a5e3df10c16be63b017653c7ba730 (patch) | |
| tree | ac5cb67a0ca331ad01a6f53df57c9125efbf97a8 /hw/s390x/css.c | |
| parent | 51af0ec9fa7269f0c69aa50a1a24748b4edc4b44 (diff) | |
| download | qemu-248b920df95a5e3df10c16be63b017653c7ba730.zip qemu-248b920df95a5e3df10c16be63b017653c7ba730.tar.gz qemu-248b920df95a5e3df10c16be63b017653c7ba730.tar.bz2 | |
s390x/css: drop data-check in interpretation
The architecture says that channel-data check is indicating that
an uncorrected storage (memory) error has been detected in regard
to the data residing in main storage (memory) that is currently
used for an I/O operation. The described detection is done using
the CBC technology.
The ccw interpretation code is however generating a channel-data check
effectively when the (device specific) ccw_cb returns -EFAULT. In case
of virtio-ccw devices this happens when mapping memory fails, or when a
NULL pointer is encountered. So this behavior is not architecture
conform.
Furthermore the best fit for these situations (null pointer, mapping a
piece of guest memory fails) from architectural perspective the condition
described as the channel subsystem refers to a location that is not
available, which when encountered shall result in a channel-program
check.
To fix this, all we have to do is to get rid of the switch case matching
-EFAULT: the default is generating a channel-program check.
Signed-off-by: Halil Pasic <pasic@linux.vnet.ibm.com>
Message-Id: <20170908152446.14606-2-pasic@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Diffstat (limited to 'hw/s390x/css.c')
| -rw-r--r-- | hw/s390x/css.c | 9 |
1 files changed, 0 insertions, 9 deletions
diff --git a/hw/s390x/css.c b/hw/s390x/css.c index 5d3de71..bab78fc 100644 --- a/hw/s390x/css.c +++ b/hw/s390x/css.c @@ -980,15 +980,6 @@ static void sch_handle_start_func_virtual(SubchDev *sch) SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND; s->cpa = sch->channel_prog + 8; break; - case -EFAULT: - /* memory problem, generate channel data check */ - s->ctrl &= ~SCSW_ACTL_START_PEND; - s->cstat = SCSW_CSTAT_DATA_CHECK; - s->ctrl &= ~SCSW_CTRL_MASK_STCTL; - s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY | - SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND; - s->cpa = sch->channel_prog + 8; - break; case -EBUSY: /* subchannel busy, generate deferred cc 1 */ s->flags &= ~SCSW_FLAGS_MASK_CC; |