Experimental Physics and
Industrial Control System

CAI MINGFU <[email protected]> · Tue, 10 Sep 1996 17:36:40 EDT

Dear Sirs,

I am working under vxWorks 5.3 with EPICS 3.13 (PC VERSION, which is from "Kay
[email protected]") and have got some errors, such as "page fault" 
with some tasks.

Seems these errors only happen when you use the version 5.3 vxWorks.

I have found the reason and here reports my modifications:

1. crash with rsrv_init(), which is invoked by iocInit()
file: ./src/rsrv/rsrv_init.c
crash with vxworks function: errnoOfTaskGet(taskId) if taskId = -1
the errnoOfTaskGet() calls _taskTcb() and if taskId is wrong 
it will cause Page Fault.
wrong:
#define DELETE_TASK(TID)\
  if(errnoOfTaskGet(TID)!=ERROR)taskDelete(TID);

corrected:
#define DELETE_TASK(TID)\
if(TID >= 0 && errnoOfTaskGet(TID)!=ERROR)taskDelete(TID);

Remark: DELETE_TASK should check TID, if not -1 then go on.

2. page fault with db scan task if no record uses its scan period
File: ./src/db/dbScan.c
function: scanList()
error: page fault with scan task if no records using this period
reason: get 'next' when pse==NULL
corrected: (line 598)
  if( pse != NULL) next = (scan_element *)ellNext((void *)pse);

3. Page Fault with spawn task req_server() in caservertask.c
file: ./src/rsrv/caservertask.c

wrong:
	accept( IOCK_sock, NULL, 0 )

corrected:
	struct sockaddr sockAddr;
	int    addLen = sizeof( sockAddr );

	accept( IOCK_sock, &sockAddr, &addLen)
Remark: accept() can not use NULL address pointer.

Now the ca is working correctly.

Best wishes,
-Cai, Mingfu (DESY-MKS2)

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System