Bug 135315

Summary: OpenIPMI libraries need IPMB mutex
Product: Red Hat Enterprise Linux 4 Reporter: Matt Domsch <matt_domsch>
Component: distributionAssignee: dff <dff>
Status: CLOSED NOTABUG QA Contact: David Lawrence <dkl>
Severity: medium Docs Contact:
Priority: medium    
Version: 4.0CC: shillman, us_linux_engineering
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OS: Linux   
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Last Closed: 2004-12-10 06:27:15 UTC Type: ---
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Description Matt Domsch 2004-10-11 21:23:32 UTC
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 
maintainer.

Dell will need Red Hat to include a future version of the OpenIPMI 
userspace libraries which address this.

Comment 3 Matt Domsch 2004-12-10 06:27:15 UTC
Per Chris Poblete in conversation with Corey Minyard, the OpenIPMI
driver already does this coordination.  Closing.