Red Hat Bugzilla – Bug 135315
OpenIPMI libraries need IPMB mutex
Last modified: 2007-11-30 17:07:13 EST
Description of problem:
The OpenIPMI userspace libraries, version 1.4.3 and below, do not
mutually exclude multiple userspace applications from issuing
commands which utilize the IPMB protocol. IPMB, a very simple 3-wire
I2C bus protocol, has very slow device semantics: commands are not
sent atomically; the command sender must wait until the device
responds; the sender must look at the sequence number of commands
that finish and determine who sent them, to pass the response back to
the proper caller. The libraries do not do this today; it is simple
for multiple IPMI library-using applications to confuse themselves
and other apps because this coordination does not occur.
Chris Poblete from Dell is speaking with the OpenIPMI maintainer,
Corey Minyard, about the proper way to solve this. Patches will be
forthcoming, and will be worked through Corey as the upstream
Dell will need Red Hat to include a future version of the OpenIPMI
userspace libraries which address this.
Per Chris Poblete in conversation with Corey Minyard, the OpenIPMI
driver already does this coordination. Closing.