IPL code, console detection, and device drivers like vmcp or vmlogrdr use
the cpcmd kernel function to send commands to the z/VM control program (CP).
If a program that uses the cpcmd function does not allocate a contiguous
response buffer in real storage, cpcmd creates a bounce buffer
to be used as the response buffer. Because of low memory or memory
fragmentation, cpcmd could not create the bounce buffer.
User response
Look for related page allocation failure messages and at the stack trace to
find out which program or operation failed. Free some memory and retry the
failed operation. Consider allocating more memory to your z/VM guest virtual
machine.