SiS900: NULL pointer encountered in Rx ring, skipping

[Dominik Karall <dominik.karall@gmx.net>]

After a few hours my network doesn't work on my laptop. There appear a lot of 
those messages:

eth0: NULL pointer encountered in Rx ring, skipping
eth0: NULL pointer encountered in Rx ring, skipping
eth0: NULL pointer encountered in Rx ring, skipping
eth0: NULL pointer encountered in Rx ring, skipping
eth0: NULL pointer encountered in Rx ring, skipping
eth0: NULL pointer encountered in Rx ring, skipping
eth0: NULL pointer encountered in Rx ring, skipping
eth0: NULL pointer encountered in Rx ring, skipping
eth0: NULL pointer encountered in Rx ring, skipping
eth0: NULL pointer encountered in Rx ring, skipping

It works again after restarting network. I'm using 2.6.8-rc2 now. It was the 
same problem in 2.6.7, but I didn't test it with earlier kernels.

And right now I got one more eth0 message:
eth0: Too much work at interrupt, interrupt status = 0x00000031.
eth0: Too much work at interrupt, interrupt status = 0x00000001.

Here the messages after module loading:
eth0: SiS 900 Internal MII PHY transceiver found at address 1.
eth0: Using transceiver found at address 1 as default
eth0: SiS 900 PCI Fast Ethernet at 0xd000, IRQ 9, 00:a0:cf:c0:8a:dc.
eth0: Media Link On 100mbps full-duplex
eth0: Memory squeeze,deferring packet.

lspci:
0000:00:01.1 Ethernet controller: Silicon Integrated Systems [SiS] SiS900 PCI 
Fast Ethernet (rev 80)
        Subsystem: Silicon Integrated Systems [SiS] SiS900 10/100 Ethernet 
Adapter
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- 
Stepping- SERR+ FastB2B-
        Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- 
<TAbort- <MAbort- >SERR- <PERR-
        Latency: 32 (13000ns min, 2750ns max)
        Interrupt: pin C routed to IRQ 9
        Region 0: I/O ports at d000 [size=ffda0000]
        Region 1: Memory at ffdc0000 (32-bit, non-prefetchable) [size=4K]
        Expansion ROM at 00020000 [disabled]
        Capabilities: [40] Power Management version 1
                Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=0mA 
PME(D0+,D1+,D2+,D3hot+,D3cold+)
                Status: D0 PME-Enable- DSel=0 DScale=0 PME-

____________
dominik