Re: BUG: kernel panic on Dell Vostro 3560 when plugging in AC adapter

[Adrian Byszuk <adrian.byszuk@gmail.com>]

On 10/01/13 12:35, Borislav Petkov wrote:
> On Thu, Jan 10, 2013 at 11:59:48AM +0100, Adrian Byszuk wrote:
>> I think I won't get the answer this way. Bisecting between
>> 3.7 and 3.8-rc2 (from linus tree) led me to commit
>> 63e1ed2364050073770c085021377d7764969b85 titled "Update vt8500 PWM
>> driver support", which I think is rather nonsense. Also, depending on
>> bisected version, sometimes I got kernel panic, but sometimes (more
>> often) whole system would just freeze completely.
>>
>> Any other way diagnose this bug?
> 
> Hmm, bisection can sometimes lead us in the fields, nasty.
> 
> Well, you could try bisecting the major releases in between. I.e., test
> 3.8-rc1, and then test vanilla 3.7.
> 
> For example, if you still trigger it with -rc1, then no need to bisect
> the -rc2..-rc1 range. If you still trigger it with 3.7 then not good -
> in that case you'd need to go further back in time.
> 
> The best would be if you don't trigger it with 3.7 but trigger it with
> 3.7.1 :) Then it is easy.

Life isn't easy :-) with 3.7 I can trigger it too, but I can't trigger
it with 3.8-rc1, so the fix lies somewhere between 3.7.1..3.8-rc1.
I'll try bisecting it again.

> 
> Also, git bisect skip can skip ranges of commits. You could try that too
> but you need to visialize how exactly the tree structure is and I admit,
> I haven't figured out the details of that yet but Linus has explained
> this approach a couple of times, you might want to take a look at this
> http://www.yarchive.net/comp/linux/git_bisect.html or search the net for
> even better ideas.
> 
> Also, you said "with 3.8.0-rc2 it looks like it's working correctly -
> I've tried the unplug/plug sequence more than 5 times and it seems to
> work fine."
> 
> Please test that again and repeat that sequence say 15-20 times, to
> make sure that -rc2 is really ok and not something changed timing and
> this bug is being only brown-paper-baggy-covered now. I mean, I'm just
> guessing - you're in front of the machine, you know best what to do to
> trigger the bug reliably.
> 
> HTH.
>