mpr0: mpr_user_pass_thru: user reply buffer (48) smaller than returned buffer (52)

[Will Dormann]

Hi folks,

I've got a FreeNAS system that has been running stably for a while. Between OS updates, hardware updates, and finally getting rid of any SATA drives (after realizing that sharing SATA and SAS on a single expander can cause unexpected problems), I can't pinpoint it down to a single change. But at some point, my daily emails from the system include some number of messages like:
mpr0: mpr_user_pass_thru: user reply buffer (48) smaller than returned buffer (52)

Occasionally, it'll be:
mpr0: mpr_user_pass_thru: user reply buffer (64) smaller than returned buffer (68)

Some times it's just a single instance of that error. Sometimes, it's hundreds. The thing is

1. I cannot Google any evidence of anybody else having had this problem.
2. There isn't any obvious evidence of the consequences of such a state. e.g., obviously-poor performance

It seems like there is something unexpected happening with the SAS3 controller and/or the two SAS expanders that are connected to it. But it's not clear to me what the cause, consequence, or solution might be.

Any ideas?

 

[dlavigne]

Were you able to find any information about this? If not, I wonder if it is worth creating a bug report at bugs.freenas.org...

 

[Will Dormann]

No, I didn't find anything. I'll file a bug...