Any subsequent attempts to start the task resulted in the same abend.
Z/OS 2.1 CA Common Services 14.1 CA Deliver 12.0
An SVCDUMP captured for all RMOSTC tasks pointed to Common Services module CAIFLOID. It was established that the module had been previously assembled and linked with the attribute RMODE=ANY, instead of RMODE=24.
The use of RMODE=ANY resulted in the module being loaded above-the-line.
The customer's SMP/E job, that had been used to apply previous maintenance, was using an incorrect OPTIONS member. It was using OPTIONS(B6DOPT), rather than OPTIONS(CAIOPT), which resulted in the module being linked with RMODE=ANY.
The client was given CSS 14.1 PTF RO96513 (and its pre-requisite PTFs) to apply, using the correct OPTIONS(CAIOPT). This resulted in a re-link of module CAIFLOID with RMODE=24, allowing the module to load below-the-line.
The module was reloaded by performing a refresh of LMP : PRODUCT(CAIRIM) VERSION(CAS9) INIT(CAS9INIT) PARM(REFRESH(LMP))
All CA Deliver RMOSTC tasks were then able to start successfully