Re: [bug] CONFIG_I2C_VIAPRO=y breaks skge

[Jean Delvare <khali@linux-fr.org>]

Hi Ingo,

On Tue, 27 Jan 2009 16:13:59 +0100, Ingo Molnar wrote:
> A -tip testsystem triggered this stuck eth0/skge bug today:
> 
>  [   24.787761] skge eth0: enabling interface
>  [   24.793177] skge eth0: phy write timeout
>  [   24.797035] skge eth0: phy write timeout
>  [   24.801019] skge eth0: phy write timeout
>  [   24.808325] skge eth0: phy write timeout
>  [   24.813019] skge eth0: phy write timeout
>  [   24.817019] skge eth0: phy write timeout
>  [   24.821131] skge eth0: phy write timeout
>  [   24.828610] skge eth0: phy write timeout
>  [   24.832834] ADDRCONF(NETDEV_UP): eth0: link is not ready
> 
>  [root@centauri ~]# ifconfig 
>  eth0     Link encap:Ethernet  HWaddr 00:0C:6E:B3:3D:C6  
>           inet addr:10.0.1.22  Bcast:10.0.1.255  Mask:255.255.255.0
>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>           RX packets:12884901885 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:12884901885 errors:0 dropped:0 overruns:0 carrier:4294967295
>           collisions:4294967295 txqueuelen:1000 
>           RX bytes:18446744073709551615 (1.5 EiB)  TX bytes:18446744073709551615 (1.5 EiB)
>           Interrupt:17 
> 
> (see the weird stats as well)
> 
> after a lengthy .config-bisection session i tracked it down to:
> 
>    CONFIG_I2C_VIAPRO=y
> 
> if that is disabled, the skge driver works fine and the stats look 
> healthy:
> 
> eth0      Link encap:Ethernet  HWaddr 00:0C:6E:B3:3D:C6  
>           inet addr:10.0.1.22  Bcast:10.0.1.255  Mask:255.255.255.0
>           inet6 addr: fe80::20c:6eff:feb3:3dc6/64 Scope:Link
>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>           RX packets:837 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:767 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:1000 
>           RX bytes:128098 (125.0 KiB)  TX bytes:130996 (127.9 KiB)
>           Interrupt:17 

Wow. This is hard to believe. The i2c-viapro driver only cares about
the SMBus interface of the VIA south bridge. I have a hard time
imagining how it could have any effect on networking.

Is the skge ethernet an on-board thing or an external adapter? I guess
the former. Do you have the detailed hardware specification for that
machine? I wonder if the ethernet chip could be somehow connected to
the SMBus.

Does the SMBus work on that machine? (Probably easier to test with
CONFIG_I2C_VIAPRO=m and CONFIG_I2C_CHARDEV=m.) I would also like to
know if there is anything in the logs when loading the i2c-viapro
driver.

What I2C chip drivers did you include in your kernel? Presumably this
is a random config, so I can imagine that there is a chip on the SMBus
to which an I2C chip driver would have bound and that is causing the
problem, rather than i2c-viapro itself.

> Find below the lspci output - it's a pretty old system. I have not tested 
> this system for a long time so the bug might have been there forever.
> 
> 	Ingo
> 
> -------------------->
> 00:00.0 Host bridge: VIA Technologies, Inc. VT8385 [K8T800 AGP] Host Bridge (rev 01)
> 00:01.0 PCI bridge: VIA Technologies, Inc. VT8237 PCI bridge [K8T800/K8T890 South]
> 00:07.0 FireWire (IEEE 1394): VIA Technologies, Inc. IEEE 1394 Host Controller (rev 80)
> 00:0a.0 Ethernet controller: 3Com Corporation 3c940 10/100/1000Base-T [Marvell] (rev 12)
> 00:0d.0 Multimedia video controller: Brooktree Corporation Bt878 Video Capture (rev 11)
> 00:0d.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture (rev 11)
> 00:0f.0 RAID bus controller: VIA Technologies, Inc. VIA VT6420 SATA RAID Controller (rev 80)
> 00:0f.1 IDE interface: VIA Technologies, Inc. VT82C586A/B/VT82C686/A/B/VT823x/A/C PIPC Bus Master IDE (rev 06)
> 00:10.0 USB Controller: VIA Technologies, Inc. VT82xxxxx UHCI USB 1.1 Controller (rev 81)
> 00:10.1 USB Controller: VIA Technologies, Inc. VT82xxxxx UHCI USB 1.1 Controller (rev 81)
> 00:10.2 USB Controller: VIA Technologies, Inc. VT82xxxxx UHCI USB 1.1 Controller (rev 81)
> 00:10.3 USB Controller: VIA Technologies, Inc. VT82xxxxx UHCI USB 1.1 Controller (rev 81)
> 00:10.4 USB Controller: VIA Technologies, Inc. USB 2.0 (rev 86)
> 00:11.0 ISA bridge: VIA Technologies, Inc. VT8237 ISA bridge [KT600/K8T800/K8T890 South]
> 00:11.5 Multimedia audio controller: VIA Technologies, Inc. VT8233/A/8235/8237 AC97 Audio Controller (rev 60)
> 00:18.0 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] HyperTransport Technology Configuration
> 00:18.1 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Address Map
> 00:18.2 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] DRAM Controller
> 00:18.3 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Miscellaneous Control
> 01:00.0 VGA compatible controller: ATI Technologies Inc RV280 [Radeon 9200 SE] (rev 01)
> 01:00.1 Display controller: ATI Technologies Inc RV280 [Radeon 9200 SE] (Secondary) (rev 01)

Can we please also have the output of lspci -nn?

Thanks,
-- 
Jean Delvare