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<DIV><FONT face=Arial size=2><SPAN class=904124115-04052006>Hi
Fab,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=904124115-04052006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=904124115-04052006>While debugging
failures in IPOIB going up on mem-free cards we have came to conclusion that
there are some race conditions, that have happened when we received the
SM_CHANGE notification many times. This message was received due to a firmware
bug, and we are taking care of it, but it seems that the handling of queries is
still problematic.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=904124115-04052006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=904124115-04052006>The problems can be
divided to two:</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=904124115-04052006>The first issue
deals with bringing the port up. We see that once queries are issued,
there is a race condition until they return. If for any reason the code of
port_down is called, there is a try to cancel the queries, however as the code
is only checking p_port->ib_mgr.h_query there is still a chance that the code
of the call back is still running. This is true for both quarries and the
request to join the QP to the broadcast group.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=904124115-04052006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=904124115-04052006>The second problem
is for endpoint lookups. It is possible that a query will go out. During this
time the port will go up and down, and the result of the (old) query will go to
the new endpoint manager.</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=904124115-04052006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=904124115-04052006>What do you
think?</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=904124115-04052006></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN
class=904124115-04052006>Thanks</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=904124115-04052006>Tzachi</SPAN></FONT></DIV></BODY></HTML>