For no obvious reason mpt2sas started to spam my system logs on a Wheezy box with an LSI SAS 9200 controller, no raid function, many disks attached) and I worried about something being broken or breaking right away. Just for the record: I would recommend this particular controller as being rock-solid and fast under heavy load.
mpt2sas0: log_info(0x30030101): originator(IOP), code(0x03), sub_code(0x0101)
Sadly, there was no useful documentation from LSI and no good hints anywhere else. Also the lsi_log_decode i stumbled upon had no clue at all. What led me to the cause of these messages was an old bug report from CentOS which finally mentioned the exact log message i got and pointed me to an issue with calls to non-existent pages from a controller related management software.
I remembered testing different cli tools. One of these was sas2ircu respectively sas2ircu-status which didn’t meet my requirements while testing, but still was installed on the system. Apparently sas2ircu-status was trying to request some information from the controller to which it responded by putting broccoli in his ears. As sas2ircu and sas2ircu-status anyway are of no use to me, the solution was to simply purge the sas2ircu* packages and hey presto, log messages stopped immediately.