I had some problems here with lirc on a new dual AMD motherboard
Tyan 'Tiger MP S2460'.
In consequence of loading the lirc_serial module via
'insmod lirc_serial' I happened to experience a total kernel lock
that could only be solved by pressing the 'reset' button.
Having a look at the kernel sources I noticed, that the sense probing
part of the code was responsable for the kernel lock (i.e. kernel
function sleep_on_timeout did obviously block) and using
'insmod lirc_serial sense=0'
solved this problem, i.e. the module was loadable now.
Nevertheless the lircd did not function properly: the first call of
e.g. 'rc SEND_ONCE ...' did function properly but obviously locked up
the lirc daemon, so that after this call:
a) any call of 'rc SEND_ONCE ...' failed with timeout
b) lircd was not stoppable any more
c) lircd could not be killed any more (even -9 failed)
d) 'rmmod lirc_serial' failed (module in use)
e) Shutdown of the system was no longer possible (probably as a
consequence of d), reset button to be used instead
Some further examination of the source code found the function
lirc_poll using kernel function poll_wait to be blamable for the hangup.
Desperately looking for a solution I decided to comment out the
corresponding 'poll_wait' function call and could indeed solve the
problem for me, since the module did not lock any more and
functionality (in my case simply as a remote control device) did not
seem to be restricted (exhaustive tests on this are still missing).
Nevertheless I have a bad feeling about this and so I decided to report
this as a bug and ask for better solutions (if available). Perhaps
there might be similar known problems with newer dual AMD boards?
For the sake of completeness:
Linux SuSE 8.0 (standard SMP kernel)
Tyan Tiger MP S2460 motherboard
2 x AMD Athlon(tm) MP Processor 1800+
512 MB DDR-Ram
Note: all the above phenomenons could be observed using lirc-0.6.4 as
well as lirc-0.6.6. Nevertheless I had some problems using version 0.6.6
since I could not get the 'rc ...' calls to function properly so I used
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