Re: [PATCH v5] fork: free vmapped stacks in cache when cpus are offline

From: Hoeun Ryu
Date: Sat Feb 11 2017 - 20:44:51 EST



> On Feb 12, 2017, at 5:19 AM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
>
>> On Sat, 11 Feb 2017, kbuild test robot wrote:
>>
>> Hi Hoeun,
>>
>> [auto build test ERROR on linus/master]
>> [also build test ERROR on v4.10-rc7 next-20170210]
>> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>>
>> url: https://github.com/0day-ci/linux/commits/Hoeun-Ryu/fork-free-vmapped-stacks-in-cache-when-cpus-are-offline/20170211-183401
>> config: ia64-allmodconfig (attached as .config)
>> compiler: ia64-linux-gcc (GCC) 6.2.0
>> reproduce:
>> wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
>> chmod +x ~/bin/make.cross
>> # save the attached .config to linux build tree
>> make.cross ARCH=ia64
>>
>> All errors (new ones prefixed by >>):
>>
>> kernel/fork.c: In function 'fork_init':
>>>> kernel/fork.c:483:2: error: implicit declaration of function 'vm_stack_cache_init' [-Werror=implicit-function-declaration]
>> vm_stack_cache_init();
>> ^~~~~~~~~~~~~~~~~~~
>
> Right. This needs to move to a different place as that part is nested inside
>
> #ifndef CONFIG_ARCH_THREAD_STACK_ALLOCATOR
>
> That's an horrible ifdef maze in that file.
>

I think we should rollback to v4. Do you agree?

> Thanks,
>
> tglx