Re: cpufreq segfaults when network cable plugged in

[Simon Cooper <thecoop@runbox.com>]

On Mon, 12 Apr 2004 10:30:58 +0200
Dominik Brodowski <linux@dominikbrodowski.de> wrote:

> On Mon, Apr 12, 2004 at 12:43:35AM +0100, Simon Cooper wrote:
> > right, this is very strange, cpufreq (compiled into the kernel) segfaults
> > whenever the network cable on my laptop is plugged in on bootup but boots
> > ok when it is plugged in after the kernel has loaded. i can post the entire
> > segfault msg but it'll need me to write it all down. driver is 'r8139'
> > (1000Mbps card), kernel version 2.6.5-mm2
> 
> Hm, this is really very strange. 
> 
> Which cpufreq drivers do you use / are compiled into the kernel?
> What are the last two to four functions called, where's the EIP at
> the segfault? [the first few function names mentioned in the oops]
> 
> Thanks,
> 	Dominik
> 

well, technically its a kernel oops (attempted ot kill init). powersave and performance govenors are compiled in, using p4_clockmod driver. Sometimes it boots fine with the cable in, but it oops's most of the time:

Unable to handle kernel NULL pointer dereference at virtual address 00000018
...
EIP: 0060:[<c02f7c45>]  Not tainted VLI
EIP is at cpufreq_notify_transition+0x79/0x98
...
Call trace:
[<c010f543>] cpufreq_p4_setdc+0x1eb/0x306
[<c01706d3>] d_lookup+0x29/0x52
[<c010f6bb>] cpufreq_p4_target+0x5d/0x69
[<c02f757d>] __cpufreq_driver_target+0x22/0x26
...

Simon