This patch contains the following linux kernel bug fix:
Description:
cio: Setting a CHPID logically offline raises an I/O error.
Symptom:
Under I/O stress, dasd posts an I/O error when a chpid has been set
logically offline.
Problem:
1. Incorrect locking of device structure in vary on/off path.
2. Out-of-date scsw used to determine if path verification could be
started immediately.
3. Dasd runs out of retries while cio is doing path verification.
Solution:
1. Fix locking in vary on/off path.
2. Update scsw by stsch() before checking for path verification
possible.
3. Seemingly accept I/O during path verification, but post a faked irb
with deferred cc 1 after path verification has finished to prompt
the driver to redrive the I/O.
Problem-ID:
12541
Everybody should apply this patch.
To create the complete linux kernel sources, the following
patches need to be applied in sequence:
