Re: Odd build breakage in 4.9-rc7

[Jarod Wilson <jarod@redhat.com>]

On 2016-11-30 4:07 PM, Jarod Wilson wrote:
> On 2016-11-30 3:52 PM, Paul Bolle wrote:
>> On Wed, 2016-11-30 at 12:24 -0500, Jarod Wilson wrote:
>>> Up second, once we're past the above, building modules goes splat:
>>>
>>> ----8<----
>>> $ make -s ARCH=x86_64 V=1 -j8 modules
>>> ...
>>> ERROR: "module_put" [virt/lib/irqbypass.ko] undefined!
>>> ERROR: "mutex_unlock" [virt/lib/irqbypass.ko] undefined!
>>> ERROR: "mutex_lock" [virt/lib/irqbypass.ko] undefined!
>>> ...
>>> ----8<----
>>>
>>> There are similar ERROR lines to the tune of 145k lines of output,
>>> basically for every single module and symbol in the build. This breakage
>>> was bisected to commit cd3caefb4663e3811d37cc2afad3cce642d60061, which
>>> looks fairly innocuous, but when reverted, builds work fine again.
>>
>> I ran into a modules build printing over 100K ERROR lines a month ago:
>>
>> https://lkml.kernel.org/r/<1478165881-9263-1-git-send-email-pebolle@tiscali.nl>
>>
>>
>> That had to do with setting TRIM_UNUSED_KSYMS and so unsetting
>> UNUSED_SYMBOLS,
>> as far as I could tell. Did you perhaps also have UNUSED_SYMBOLS unset
>> when
>> your modules build when splat?
>
> I did indeed have CONFIG_TRIM_UNUSED_KSYMS=y and CONFIG_UNUSED_SYMBOLS
> unset.

Just to confirm, with CONFIG_TRIM_UNUSED_KSYMS unset, the build behaves 
normally, no ERROR spew.

-- 
Jarod Wilson
jarod@redhat.com