Massive log spam loading modules on ARM after 3.2-rc5 (regression)

Russell King - ARM Linux linux at
Thu Dec 15 03:31:15 EST 2011

On Thu, Dec 15, 2011 at 09:02:13AM +0100, Uwe Kleine-König wrote:
> On Wed, Dec 14, 2011 at 04:51:33PM -0500, Nick Bowler wrote:
> > The message only seem to get printed at module load time.  Other than
> > the noise, things _seem_ to be working.  Nevertheless, it's a regression
> > introduced after 3.2-rc5 by the following commit:
> > 
> >   de66a979012dbc66b1ec0125795a3f79ee667b8a is the first bad commit
> >   commit de66a979012dbc66b1ec0125795a3f79ee667b8a
> >   Author: Uwe Kleine-König <u.kleine-koenig at>
> >   Date:   Mon Dec 5 09:39:59 2011 +0100
> > 
> >       ARM: 7187/1: fix unwinding for XIP kernels
> > 
> >       The linker places the unwind tables in readonly sections. So when using
> >       an XIP kernel these are located in ROM and cannot be modified.
> >       For that reason the current approach to convert the relative offsets in
> >       the unwind index to absolute addresses early in the boot process doesn't
> >       work with XIP.
> > 
> >       The offsets in the unwind index section are signed 31 bit numbers and
> >       the structs are sorted by this offset. So it first has offsets between
> >       0x40000000 and 0x7fffffff (i.e. the negative offsets) and then offsets
> >       between 0x00000000 and 0x3fffffff. When seperating these two blocks the
> >       numbers are sorted even when interpreting the offsets as unsigned longs.
> > 
> >       So determine the first non-negative entry once and track that using the
> >       new origin pointer. The actual bisection can then use a plain unsigned
> >       long comparison. The only thing that makes the new bisection more
> >       complicated is that the offsets are relative to their position in the
> >       index section, so the key to search needs to be adapted accordingly in
> >       each step.
> > 
> >       Moreover several consts are added to catch future writes and rename the
> >       member "addr" of struct unwind_idx to "addr_offset" to better match the
> >       new semantic. (This has the additional benefit of breaking eventual
> >       users at compile time to make them aware of the change.)
> > 
> >       In my tests the new algorithm was a tad faster than the original and has
> >       the additional upside of not needing the initial conversion and so saves
> >       some boot time and it's possible to unwind even earlier.
> > 
> >       Acked-by: Catalin Marinas <catalin.marinas at>
> >       Acked-by: Nicolas Pitre <nico at>
> >       Signed-off-by: Uwe Kleine-König <u.kleine-koenig at>
> >       Signed-off-by: Russell King <rmk+kernel at>
> > 
> >   :040000 040000 9c4363228515808d71dac84a4a16e0aa0cf4ceaa 65b80d4e51fabf0a3142a880be795f4b38f4d9fe M	arch
> > 
> > I am *not* using XIP.  Reverting this commit resolves the issue.
> I'd say revert that change for now, I'll take a look. (IMHO this is
> merge window material even though it has "fix" in the title. The
> addressed problem is only relevant on XIP (which isn't used much AFAIK)
> and is broken since 2.6.30-rc1~636^2~52^2~18 when unwinding was
> introduced.)

For christ sake Uwe, stop being an idiot.  If that's the case then
YOU NEED TO SAY which kernel you want the patch applied to, and not
leave it up to chance.  Nothing in that says "this should not go
into -rc".

And wtf wasn't it tested with modules?

Congratulations, your incompetence will now have consequences.  I'm
*not* going to apply any patch from you in future for -rc without
there being _several_ tested-by's from various people.  So you're
going to find it harder to get patches in.

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