Re: [PATCH v5 03/20] kthread: Add create_kthread_worker*()

[Petr Mladek]

On Mon 2016-02-22 23:48:53, kbuild test robot wrote:
> Hi Petr,
> 
> [auto build test ERROR on soc-thermal/next]
> [also build test ERROR on v4.5-rc5 next-20160222]
> [if your patch is applied to the wrong git tree, please drop us a note to help improving the system]
> 
> url:    https://github.com/0day-ci/linux/commits/Petr-Mladek/kthread-Use-kthread-worker-API-more-widely/20160222-230250
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal next
> config: xtensa-allyesconfig (attached as .config)
> 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=xtensa 
> 
> All error/warnings (new ones prefixed by >>):
> 
>    kernel/kthread.c: In function 'create_kthread_worker_on_cpu':
> >> kernel/kthread.c:691:9: error: incompatible type for argument 3 of '__create_kthread_worker'
>      return __create_kthread_worker(cpu, namefmt, NULL);
>             ^
>    kernel/kthread.c:622:1: note: expected 'va_list' but argument is of type 'void *'
>     __create_kthread_worker(int cpu, const char namefmt[], va_list args)
>     ^
> >> kernel/kthread.c:692:1: warning: control reaches end of non-void function [-Wreturn-type]
>     }
>     ^
> 
> vim +/__create_kthread_worker +691 kernel/kthread.c
> 
>    685	 * when the needed structures could not get allocated, and ERR_PTR(-EINTR)
>    686	 * when the worker was SIGKILLed.
>    687	 */
>    688	struct kthread_worker *
>    689	create_kthread_worker_on_cpu(int cpu, const char namefmt[])
>    690	{
>  > 691		return __create_kthread_worker(cpu, namefmt, NULL);
>  > 692	}
>    693	EXPORT_SYMBOL(create_kthread_worker_on_cpu);
>    694	
>    695	/* insert @work before @pos in @worker */

I can be fixed by passing a fake va_list. It is not used when
__create_kthread_worker() is called with a valid CPU number.

See below an updated patch that passes the build.