Re: [crash] BUG: unable to handle kernel NULL pointer dereference at 0000000000000370

Ingo Molnar
2008-07-21T19:35:53Z

* Larry Finger <Larry.Finger@lwfinger.net> wrote:

> Ingo Molnar wrote:
>> * Ian Schram <ischram@telenet.be> wrote:
>>
>>> I was looking at this out of interest, but I'm in no way familiar
>>> with the code.
>>
>> thanks Ian for the patch, i'll test it.
>>
>> Note that it was whitespace damaged, find below a tidied up version of
>> the patch that i've applied to tip/out-of-tree.
>>
>> Ingo
>
> This patch may be needed to fix error handling in the hw_sim code, but
> I get the crash even with that code disabled. I'm currently bisecting
> to find the culprit.

ok. I just reactivated CONFIG_MAC80211_HWSIM, applied Ian's fix and the
crash went away:

calling iwl4965_init+0x0/0x6c
iwl4965: Intel(R) Wireless WiFi Link 4965AGN driver for Linux, 1.3.27kd
iwl4965: Copyright(c) 2003-2008 Intel Corporation
initcall iwl4965_init+0x0/0x6c returned 0 after 10 msecs
calling init_mac80211_hwsim+0x0/0x31c
mac80211_hwsim: Initializing radio 0
PM: Adding info for No Bus:hwsim0
PM: Adding info for No Bus:phy0
PM: Adding info for No Bus:wmaster0
phy0: Failed to select rate control algorithm
phy0: Failed to initialize rate control algorithm
PM: Removing info for No Bus:wmaster0
PM: Removing info for No Bus:phy0
mac80211_hwsim: ieee80211_register_hw failed (-2)
PM: Removing info for No Bus:hwsim0
initcall init_mac80211_hwsim+0x0/0x31c returned -2 after 58 msecs
initcall init_mac80211_hwsim+0x0/0x31c returned with error code -2
calling dmfe_init_module+0x0/0xea
dmfe: Davicom DM9xxx net driver, version 1.36.4 (2002-01-17)
initcall dmfe_init_module+0x0/0xea returned 0 after 5 msecs

So at least as far as the init_mac80211_hwsim() deinit crash goes:

Tested-by: Ingo Molnar <mingo@elte.hu>

Ingo