Re: 3.13: BUG: unable to handle kernel paging request at00000000b4343e88

From: Meelis Roos
Date: Tue Jan 28 2014 - 01:33:43 EST


> >>>> It looks like gcov exploded when running a module's constructors or
> >>>> init function, but I'm unable to work out which module it was :(
> >>> [...]
> >>>
> >>>> Maybe it's tg3.
> >>>>
> >>>> Could you add `ignore_loglevel' to the kernel boot parameters? That
> >>>> should make all pr_debug()s come out and they include the module's
> >>>> name.
> >>
> >> I'm not sure if this related, but all 3 kernel logs consistently contain
> >> this error message:
> >>
> >>> [ 0.617401] gcov: could not create file
> >>
> >> which should only be shown in case of severe out-of-memory situations or
> >> duplicate object file names.
> >>
> >> Could you retry with the following patch applied (2 times if possible)
> >> and send dmesg output?
> >
> > This seems to be relevant - now there is a reproducible crash during the
> > printk. Captured end of the backtrace from HP ILO as image, attached.
> > This is reproducible.
>
> Ok, that's a lead. It appears that gcov-kernel receives gcov_info
> structures in an unexpected format. Based on your previous dmesg output,
> your kernel was compiled using gcc 4.7.2 which gcov-kernel should be able
> to handle just fine. Could you please try out this debugging patch
> (replacing the previous one)? Output will likely be quite verbose, so you
> might consider using log_buf_len=1M or similar as kernel parameter.

I do not get very far - it still crashes on startuo. PNG attached.

--
Meelis Roos (mroos@xxxxxxxx)

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