In cases where an application issues certain IPMI commands at a high
enough rate, the IPMI code can print large numbers of messages to the
console, such as:

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

These seem to be innocuous from a system standpoint, and the user-
space code can deal with the failures. Therefore, suppress printing
these messages to the console unless bootverbose is enabled.

Obtained from: Netflix, Inc.