066

Explanation
The dispatcher of tasks and service routines detected
an error. A hexadecimal reason code in register 15 explains the error: Code
Explanation
04
A completed routine that ran under a service request block (SRB)
held a system lock when it returned to the dispatcher.
0C
A routine that ran under a suspended service request block (SSRB)
held the cross memory local (CML) lock of a failing address space.
The ASCBFAIL bit is on. The ASCBFAIL bit is in the address space control
block (ASCB) of the failing address space.
10
The SRBASCB field of an SRB or an SSRB points to an ASCB that
has an erroneous acronym.
14
A task holds the CML lock of a failing address space. The ASCBFAIL
bit for the failing address space is on.
18
Status could not be saved for the current task due to an error
in the dispatcher.
1C
A task attempted to reenter the dispatcher through the SRB entry
point.
20
A routine that ran under an SRB attempted to reenter the dispatcher
through a task entry point.
24
Status could not be saved for the current SRB due to an error
in the dispatcher.
28
Task could not be dispatched because the CML lock was stolen.
2C
IEA0DS1B was entered not in wait mode.

System action
The system abends the task or SRB and
may write a logrec data set error record.

Operator response
If the system programmer asks for an SVC dump,
set the following SLIP trap: SLIP SET,ENABLE,COMP=066

System programmer response
Do the following: For reason code X'04', go to step 3.
For any other reason code, go to step 6.
For reason code X'04', if a logrec data set
error record is not written with the abend, ask the operator to set
a SLIP trap to obtain an SVC dump. Format the dump to see: Register 2 through register 8
Register 10 through register 13
These are the SRB routine's registers at the time it gave
up control.

Check these registers to see if one looks like a base
register, as follows. Look for a group of registers containing addresses
near the same place in storage. If you find such a group of registers,
look for the register with the lowest address. This is possibly a
base register. Identify the module that is using this register as
its base register.
Determine which lock was held when the problem occurred.
The current lock held string can be found in two different places: Register 14 at the time of error
In the PSACLHS field of the SVCE D trace entry for abend X'066'

Search problem reporting data bases for a fix for the
problem. If no fix exists, and an SVC dump has not be obtained, ask
the operator to set a SLIP trap to obtain an SVC dump. Contact the IBM® Support Center. Provide: The SVC dump
The system trace
The logrec data set error record, if available

Source
Supervisor control