FreeBSD nfe driver and IPMI cards
pyunyh at gmail.com
Tue Sep 11 17:49:19 PDT 2007
On Tue, Sep 11, 2007 at 03:01:53PM -0400, Robert Wojciechowski wrote:
> I'm the FreeBSD nfe driver from
> with FreeBSD 6-stable with good results for the most part. The only
> issue I've experienced is that during a detach/shutdown of if_nfe, the
> IPMI IP address I have set on my servers ceases to respond as well as
> the ability to manage the servers.
> I traced the problem down to nfe_stop() and the fact that it completely
> disables the Rx and Tx on the NIC. I have patched the driver to not
> disable the Rx/Tx and IPMI continues to work after a 'ifconfig nfe0
> down', 'shutdown -p now', etc.
> Does anyone have any comments on this change I've made and any possible
> side effects? Can this be included in the mainstream distribution of the
Because MAC is still alive if's possible to recieve a packet. All DMA
maps are unloaded and buffers are already freed in nfe_stop so it
would cause panic I guess. But I'm not familiar with IPMI so I'm not
> nfe drivers (and updated in 7-CURRENT) without causing any adverse
I have no experience on IPMI but the change you've made would not
completely solve the issue. I guess supporting IPMI needs lots of
more work including:
o Autodetect IPMI capability.
o Autodetect active IPMI session in device attach and don't blindly
o Don't blindly stop Tx/Rx on device detach.
Given that lack of publicly available datasheet for the hardware
supporing IPMI would be severly limited. Fortunately Linux seems to
have basic IPMI support in their forcedeth driver. Their code doesn't
easy to read but you may see what should be done in driver. However
I have no idea what we can do when active IPMI session is present in
driver attach phase. Normally PHY driver would reset PHY hardware
itself in driver attach which in turn would result in losing the IPMI
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