Problem with IPMI KCS driver

[Anton Yuzhaninov]

On 28.09.2012 16:48, John Baldwin wrote:
>> kcs_wait_for_obf() at kcs_wait_for_obf+0xb6 point to
>> >  /usr/src/sys/dev/ipmi/ipmi_kcs.c:94
>> >
>> >     91                 while (ticks - start<  MAX_TIMEOUT&&
>> >     92                     !(status&  KCS_STATUS_OBF)) {
>> >     93                         DELAY(100);
>> >     94                         status = INB(sc, KCS_CTL_STS);
>> >     95                 }
> Hummm.  I'm a bit out of ideas then.  Even the volatile change is a bug that
> could have been confirmed (to see if volatile was preventing the compiler
> from caching the value of 'ticks') by examining the assembly.
>
> Well, maybe this.  This just avoids using 'ticks' altogether and depends on
> DELAY(100) doing what it says:

New patch also don't solve my problem.

My guess was wrong. Loop in kcs_wait_for_obf() is not endless, at least with 
last patch.
Whole function called in some loop, but because loop in kcs_wait_for_obf() takes 
much CPU time, backtrace always point to loop kcs_wait_for_obf().

This problem need further investigation.

-- 
  Anton Yuzhaninov