Re: [PATCH 3.14 000/140] 3.14.5-stable review

Guenter Roeck
2014-05-30T17:14:33Z

On 05/29/2014 02:27 PM, Linus Torvalds wrote:
> On Thu, May 29, 2014 at 2:07 PM, Guenter Roeck <linux@roeck-us.net> wrote:
>> On Thu, May 29, 2014 at 11:21:09AM -0700, Greg Kroah-Hartman wrote:
>>> On Thu, May 29, 2014 at 08:06:10AM -0700, Guenter Roeck wrote:
>>>>
>>>> alpha:defconfig - Fails with 'Inconsistent kallsyms data'. New failure; need to debug.
>>>>
>>>> Bisect points to commit 'vlan: Fix lockdep warning with stacked vlan devices' as culprit
>>>> for the alpha:defconfig build failure. Reverting this patch fixes the problem.
>>>> I looked at the patch, but I have no idea what may cause the failure.
>>>
>>> Odd. Is this also broken in Linus's tree?
>>>
>> Agreed, it is odd. As I said, not idea what is causing this.
>> v3.15-rc7 is fine.
>
> The bisection is almost certainly bogus, and this 'inconsistent
> kallsyms data' issue is not new. I thought we fixed it, but it's
> possible that there are alpha-specific issues and/or that it depends
> on binutils versions.
>
> In particular, when we've seen it in the past, it has depended on
> exact alignment of code or data, which is why random changes
> (particularly to percpu data) can seem to trigger it. Basically, two
> symbols getting the same address and then being sorted differently by
> 'nm' or similar.
>
> See for example
>
> http://marc.info/?l=linux-next&m=133267456809502&w=2
>
> where it hits ARM and rmk actually debugged that particular case.
>
> Adding Michal to the cc, because I have a dim memory of this being
> fixed, but I can't remember how. I hope Michal does.. Or maybe the
> fact that alpha is hit by this just means that I mis-remember.
>

For now I "solved" the build problem by adding KALLSYMS_EXTRA_PASS=1"
to alpha builds.

Guenter