Wait
CP Disabled Wait
No processing occurs in the virtual machine when it is in a wait state. When the
wait state is an enabled one, an I/O interrupt causes processing to resume. Like­
wise, when the Control Program is in a wait state, its processing ceases.
A disabled wait state usually results from a hardware malfunction. During the IPL process, normally correctable hardware errors may cause a wait state because the
operating system error recovery procedures are not accessible at this point. These
conditions are recorded in the current PSW. CP may be in an enabled wait state with channel a disabled when it is attempting
to acquire more free storage. Examine EC register 2 to see whether or not the
multiplexer channel is disabled. A severe machine check could also cause a CP dis­
abled wait state.
Three types of severe machine checks can cause the VM/SP Control Program to
terminate or cause a CP disabled wait state.
An unrecoverable machine check in the control program • A machine check that cannot be diagnosed
Timing facilities damage
A machine check error cannot be diagnosed if either the machine check old PSW or
the machine check interrupt code is invalid. These severe machine checks cause
the control program to terminate.
If a severe machine check or channel check caused a CP disabled wait state, one of
the following messages appears:
DMKCCH603 CHANNEL ERROR, RUN SEREP, RESTART SYSTEM
DMKMCH612W MACHINE CHECK TIMING FACILITIES DAMAGE; RUN SEREP
DMKMCT612W MACHINE CHECK TIMING FACILITIES DAMAGE; RUN SEREP
If an unrecoverable machine check occurs in the control program, the message
DMKMCH610W MACHINE CHECK SUPERVISOR DAMAGE
--or--
DMKMCT610W MACHINE CHECK SUPERVISOR DAMAGE
appears on the processor console. The control program is terminated and enters a
wait state 001 or wait state 013. If the machine check handler cannot diagnose a certain machine check, the integri­
ty of the system is questionable. The message
DMKMCH611W MACHINE CHECK SYSTEM INTEGRITY LOST --or--
DMKMCT611W MACHINE CHECK SYSTEM INTEGRITY LOST Introduction to Debugging 485

appears on the processor console. The control program is terminated and enters
wait state 001 or wait state 013. Hardware errors are probably the cause of these severe machine checks. The sys­ tem operator should run the CPEREP program and save the output for the installa­
tion hardware maintenance personnel.
If the generated system cannot run on the real machine because of insufficient
storage, CP enters the disabled wait state with code OOD in the PSW. The insuffi­
cient storage condition occurs if:
The generated system is larger than the real machine size
--or--
A hardware malfunction occurs which reduces the available amount of real
storage to less than that required by the generated system
The message
DMKCPI955W INSUFFICIENT STORAGE FOR VM/SP appears on the processor console.
If CP cannot continue because consecutive hardware errors are occurring on one or
more VM/SP paging devices, the message
DMKPAG415E CONTINUOUS PAGING ERRORS FROM DASD xxx
appears on the processor console and CP enters the disabled wait state with code OOF in the PSW. If more than one paging device is available, disable the device on which the hard­
ware errors are occurring and IPL the system again. If the VM/SP system is
encountering hardware errors on its only paging device, move the paging volume to
another physical device and IPL again.
Note: This error condition may occur if the VM/SP paging volume was not proper­
ly formatted.
The following procedure should be followed by the processor operator to record
the needed information.
1. Using the alter/display mode of the processor console, display the real PSW and CSW. Also, display the general registers and the control registers.
2. Force a CP system restart in order to get a system abend dump.
3. IPL the system.
Examine this information and attempt to find what caused the wait. If you cannot
find the cause, attempt to reconstruct the situation that existed just before the wait
state was entered.
486 VM/SP System Programmer's Guide