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<DIV><SPAN class=148355217-05012009><FONT face=Arial><FONT size=2>Hello all<SPAN
class=281264208-06012009> and Happy New Year!</SPAN></FONT></FONT></SPAN></DIV>
<DIV><SPAN class=148355217-05012009><FONT face=Arial><FONT size=2><SPAN
class=281264208-06012009></SPAN></FONT></FONT></SPAN> </DIV>
<DIV><SPAN class=148355217-05012009><FONT face=Arial size=2>Recently, we found
the following problem: When restarting a subnet manager (say, opensm), IPoIB
will be not aware of this. At a fact, IPoIB doesn't receive "REREGISTER" or
"<SPAN class=281264208-06012009>LI</SPAN>D CHANGED" events. This can lead to
connectivity problems (like "no ping" etc.). Below is the
description:</FONT></SPAN></DIV>
<DIV><SPAN class=148355217-05012009><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=148355217-05012009><FONT face=Arial size=2>1. SM is in charge
to update the appropriate bit in port_info.</FONT></SPAN></DIV>
<DIV><SPAN class=148355217-05012009><FONT face=Arial size=2>2. It's indeed
performed and then external SMA receives this infomation and transfers it to
a mlx4_bus.</FONT></SPAN></DIV>
<DIV><SPAN class=148355217-05012009><FONT face=Arial size=2>3. Now, mlx4_bus
generates events appropriate event (L<SPAN class=281264208-06012009>I</SPAN>D
CHANGED), and his subscriber, mlx4_hca receives it.</FONT></SPAN></DIV>
<DIV><SPAN class=148355217-05012009><FONT face=Arial size=2>4. Now, the
information should pass to IBAL and then to IPoIB. Practically, the event
notification mechanism is not implemented for this case.</FONT></SPAN></DIV>
<DIV><SPAN class=148355217-05012009><FONT face=Arial size=2>That is, information
about change in the lead will never leave HW driver.</FONT></SPAN></DIV>
<DIV><SPAN class=148355217-05012009><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=148355217-05012009><FONT face=Arial size=2>Our observation and
proposed solution:</FONT></SPAN></DIV>
<DIV><SPAN class=148355217-05012009>
<DIV><SPAN class=583022808-04012009><FONT face=Arial><FONT size=2><SPAN
class=148355217-05012009>In </SPAN>order to receive notifications<SPAN
class=148355217-05012009> o</SPAN>n the<SPAN class=148355217-05012009>
"event_handler"</SPAN> function, one has to call
mlnx_register_event_handler which in-turn means that one has to call
register_event_handler. Currently only the <SPAN
class=148355217-05012009>one ULP -</SPAN>winverbs is calling this
function.</FONT></FONT></SPAN></DIV>
<DIV><SPAN class=583022808-04012009><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><FONT size=2><SPAN class=583022808-04012009>
<DIV><FONT face=Arial><SPAN class=583022808-04012009>On the other side, the core
is being called<SPAN class=281264208-06012009> on the Linux side</SPAN>, and it
dispatches the information to it's users. </SPAN></FONT></DIV>
<DIV><FONT face=Arial><SPAN class=583022808-04012009></SPAN></FONT> </DIV>
<DIV><SPAN class=583022808-04012009><FONT face=Arial><SPAN
class=148355217-05012009>In our humble opinion,</SPAN> IBAL is <SPAN
class=947093608-06012009>currently </SPAN>missing this functionality<SPAN
class=148355217-05012009>. </SPAN></FONT></SPAN></DIV>
<DIV><FONT size=+0><FONT face=Arial size=2><SPAN class=583022808-04012009><SPAN
class=148355217-05012009><SPAN class=947093608-06012009>We plan to add this
mechanism to IBAL in order to have the ULPs aware of this change.
</SPAN></SPAN></SPAN></FONT></FONT></DIV>
<DIV><FONT size=+0><FONT face=Arial size=2><SPAN class=583022808-04012009><SPAN
class=148355217-05012009><SPAN class=947093608-06012009>The dispatching of this
messages will be done by the existing IBAL pnp
mechanism.</SPAN></SPAN></SPAN></FONT></FONT></DIV></SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=583022808-04012009><SPAN
class=148355217-05012009></SPAN></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=583022808-04012009><SPAN
class=148355217-05012009>Thanks,</SPAN></SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN class=583022808-04012009><SPAN
class=148355217-05012009>XaleX</SPAN></SPAN></FONT></DIV></SPAN></DIV></DIV></BODY></HTML>