"ipmi0: KCS..." whines

[David Wolfskill]

I'm trying to figure out how to cope with some messages:

... kernel: ipmi0: KCS: Failed to read completion code
... kernel: ipmi0: KCS error: ff

that recently started showing up on some machines at work (which run
somethinng based on FreeBSD).

As the messages started showing up shortly after a colleague committed
some code that would issue "ipmitool dcmi power reading" periodically, I
tried issuing the command myself... to no (initial) effect.

I then tried doing it in a loop:

foreach n (`jot 10`)
ipmitool dcmi power reading
end

Nothing.  But then, 10 isn't a very big number, so I tried again with 32
-- and got a few.

That said, I have seen no evidence of data corruption or mis-reporting
that coincides with the messages being issued: at this point, the
messages seem to merely be annoying, and there's nothing I can do to
stop getting them (except to not issue "ipmitool dcmi power reading",
perhaps).

Also, I have no real evidence that whatever is causing the messages to
be issued "in real life" is actually related to my "articial" recreation
of the symptoms.

I poked around a bit, and found that the messages are issued from
src/sys/dev/ipmi/ipmi_kcs.c, where device_printf(9) is used to emit
them.  (Eventually, that gets around to using printf(9), which is why I
was unable to merely use syslog.conf to stop spamming the console.)

As a proof-of-concept, I cobbled up the attached patch (with significant
help from a colleague).  It seems to do as intended: suppress the
messages for a "normal" boot, but emit them for a verbose boot.

I'm not at all happy with that approach: it's way too far on the
"treating the symptom" side than "fixing the root cause."  On the other
hand, it's not clear that emitting a message about which I can do
nothing useful is all that ... useful. :-}

But ... none of the machines to which I have access and have the
requisite hardware are running stock FreeBSD.

Is anyone able to reproduce this on a stock FreeBSD machine?

Better: anyone have a better idea how to address thhe issue?

Thanks!

Peace,
david
-- 
David H. Wolfskill				david at catwhisker.org
Those who would murder in the name of God or prophet are blasphemous cowards.

See http://www.catwhisker.org/~david/publickey.gpg for my public key.
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