The logic in css_interpret_ccw() correctly returns -EINVAL if a
Transfer-In-Channel (TIC) CCW is command chained to another TIC CCW.
The same routine also correctly returns -EINVAL if 256 CCWs do not
perform a data transfer as part of the I/O operation [0].
What is missing, however, is a combination of these two, where a loop
can be generated that will continue processing CCWs but without
providing an opportunity to catch a breath. Fix this by capping
the number of TIC CCWs in a channel program at the same limit as
the CCWs without data transfer.
[0] See "Invalid Sequence" in z/Architecture Principles of Operation
(SA22-7832-14), p16-27
Cc: qemu-stable@nongnu.org
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Message-ID: <20260713074708.884282-1-borntraeger@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
33bece0fa1