#2804 BLOC First D: Cursor sometimes goes strange

[Zarro Boogs per Child]

#2804: Cursor sometimes goes strange
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  Reporter:  philipmac        |       Owner:  bernie                
      Type:  defect           |      Status:  assigned              
  Priority:  blocker          |   Milestone:  First Deployment, V1.0
 Component:  x window system  |     Version:                        
Resolution:                   |    Keywords:                        
  Verified:  0                |  
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Comment(by bernie):

 As we all know, this bug is hard to reproduce, and tends to disappear when
 we try to instrument our code.

 I'm working on the assumption that this bug, or at least one of its forms,
 is stateful: it's either "on" or "off" for a long time.  So I'm looking
 for places where the PS2 code maintains context in global variables.

 I have already reviewed the kernel side of the protocol, without spotting
 any obvious place where we may hold context.

 The EC firmware appears to relay the PS2 data in passthrough, without
 doing any interpretation on it.  Therefore, I think we may exclude it from
 our list of suspects.

 So I'm getting suspicious at the keyboard and touchpad microcontroller,
 for which we have no source code.  It would be nice if we could get it
 from Quanta, or ask them to do a similar review and report their findings.

 Another useful test would be resetting the uC while the bug is "on" and
 see whether the bug survives or not.

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Ticket URL: <https://dev.laptop.org/ticket/2804#comment:29>
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