By checking the results of errors on SSCH in the kvm-unit-tests
We noticed that no error was reported when a SSCH is started
to access addresses not existing in the guest.
For exemple accessing 3G on a guest with 1G memory.

If we look at QEMU ccw_dstream_write/write functions we see that they
are often not checked for error in various places.

It follows that accessing an invalid address does not trigger a
subchannel status program check to the guest as it should.

Regards,
Pierre


Pierre Morel (1):
  s390x: css: report errors from ccw_dstream_read/write

 hw/char/terminal3270.c | 11 +++++--
 hw/s390x/3270-ccw.c    |  5 +++-
 hw/s390x/css.c         | 14 +++++----
 hw/s390x/virtio-ccw.c  | 66 ++++++++++++++++++++++++++++++------------
 4 files changed, 69 insertions(+), 27 deletions(-)

-- 
2.17.1

changelog:

from v1:

- handle_payload_3270_read, return CSS error on CSS access errors
  keep returning -EIO for other 3270 internal errors.
  (Connie)

- css_interpret_ccw, let CSS handle the residual count even on errors
  it is supposed to do it right.
  (Connie)