Intel 82574L, issues with 10.6.4 - can anyone confirm?

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Hi there,

 

I'm experiencing some weird behaviour with a Snow Leopard installation from scratch; my source is a vanilla 10.6.3 build 10D575 retail DVD.

 

The system works perfectly with 10.6.3, the only thing I have to edit to make my Intel 82574L work is the VID:PID as explained inter alia here.

 

However after the update to 10.6.4 (and of course having patched the Info.plist again), the madness begins. The driver gets loaded properly:

kernel[0]: Intel82574L::start - Built May 4 2010 10:31:05 -- running on device at b3d0f0

kernel[0]: DSMOS has arrived

kernel[0]: Intel82574L: Ethernet address 00:1b:de:ad:ca:fe

kernel[0]: Ethernet [intel82574L]: Link up on en0, 1-Gigabit, Full-duplex, No flow-control, Debug [796d,ac48,0de1,0200,c1e1,2800]

The system aquires an IP via DHCP, I can ping internal and external IPs, DNS resolution works properly, too. However, as soon as the NIC gets utilized noteworthy (firing up Apple Safari or the Software update is sufficient), the connection fails with no hint at all in the logs. OS X claims to be still connected (green icon in network preferences), but any attempt to connect anything except for 127.0.0.1 fails. When I try to renew the DHCP adress at this point of time, OS X assigns itself an internal IP.

 

The bottom line: 82574L networking appears to work with 10.6.4, but fails with the slightest load.

 

Any hints? Thanks in advance!

 

EDIT: Some more information, including download for the working 10.6.3 and the non-working 10.6.4 kexts, here.