Re: [GIT PULL] s390 patches for the 3.15 merge window

[Martin Schwidefsky <schwidefsky@de.ibm.com>]

On Tue, 1 Apr 2014 08:40:41 -0700 (PDT)
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> 
> 
> On Tue, 1 Apr 2014, Martin Schwidefsky wrote:
> > 
> > I gave up after a few hours trying to solve the header dependencies, the two
> > trouble makes are alpha with the task_thread_info call in mmu_context.h and
> > arm with the preempt_enable_no_resched call. Welcome to include file hell.
> 
> I don't understand. The only file <asm/mmu_context.h> should need is 
> <linux/mm.h>. Maybe <kernel/sched.h>.
> 
> Look at mm/mmu_context.c, for example. It includes <asm/mmu_context.h> 
> without having included very many header files at all. So we *know* that 
> that small set is sufficient. 
> 
> And there aren't very many users of <linux/mmu_context.h> and none of them 
> are other header files, so there's no point in trying to religiously avoid 
> including one or two header files from it.
> 
> So I'm thinking something like this should work. It's untested, and maybe 
> some architecture really needs some other header file, but it looks quite 
> likely to work. No?

I had a patch quite similar to yours and I ended up with the error report
from the kbuild robot. Just tried yours with the corgi_defconfig and got
this:

In file included from include/linux/mmu_context.h:6,
                 from drivers/usb/gadget/inode.c:27:
/home4/mschwide/linux/arch/arm/include/asm/mmu_context.h: In function 'finish_arch_post_lock_switch':
/home4/mschwide/linux/arch/arm/include/asm/mmu_context.h:82: error: implicit declaration of function 'preempt_enable_no_resched'

Part of the problem is this lovely piece from include/linux/preempt.h:

#ifdef MODULE
/*
 * Modules have no business playing preemption tricks.
 */
#undef sched_preempt_enable_no_resched
#undef preempt_enable_no_resched
#undef preempt_enable_no_resched_notrace
#undef preempt_check_resched
#endif

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.