The atl1c driver shipped with sys-kernel/gentoo-sources-2.6.32-r2 (and earlier kernels too) does not work.
The easiest way to trigger this problem is to configure a machine to act as an NFS server and then to access a large file, for example "md5sum /net/nas/ISO/livecd-i686-installer-2008.0-r1.iso"
In my case, small transfers work fine (I can "ls -al /net/nas/ISO"), however heavy activity causes the driver to fail. There are no errors, however no data is sent. Using ifconfig, I can see that the RX/TX figures are not increasing.
If I unload the atl1c module, insert a Realtek based PCI card and use the r8169 driver, the NFS server/client configuration works fine.
Ubuntu bug database seems to suggest that they also experience this problem and some users have reported that Atheros may have an updated driver available from their corporate website.
Can you post the link from the Ubuntu bug, please.
This patch look to be included in 184.108.40.206 which has been in the last two gentoo-sources.
Please test the latest 2.6.32 gentoo sources which is 2.6.32-r4 as of this writing.
The Ubuntu bug is 512764
I'll try the latest Gentoo sources as soon as I have physical access to the machine, which should be in about 5 days.
Retested with sys-kernel/gentoo-sources-2.6.32-r5 and it is still broken with same symptoms.
Seems to be a bit of activity on this driver. Can you test with git-sources-2.6.33-rc8.
please test with 2.6.33 and reopen with the results if you still have issues. This might need to go upstream
Tested with sys-kernel/gentoo-sources-2.6.33 and problem seems to be fixed.