On Tue, 1 Jul 2008, Adrian Bunk wrote:

On Tue, Jul 01, 2008 at 08:46:54AM -0400, Dmitry Torokhov wrote:

quoted

On Tue, Jul 01, 2008 at 01:55:25PM +0200, Geert Uytterhoeven wrote:

quoted

commit 656acd2bbc4ce7f224de499ee255698701396c48
Author: Dmitry Torokhov [off-list ref]
Date:   Thu Jun 26 11:30:02 2008 -0400

    Input: fix locking in force-feedback core

    The newly added event_lock spinlock in the input core disallows sleeping
    and therefore using mutexes in event handlers. Convert force-feedback 
    core to rely on event_lock instead of mutex to protect slots allocated  
    for fore-feedback effects. The original mutex is still used to serialize
    uploading and erasing of effects.

causes the following regression on m68k:

| linux/drivers/input/ff-core.c: In function 'input_ff_upload':
| linux/drivers/input/ff-core.c:172: error: dereferencing pointer to incomplete type
| linux/drivers/input/ff-core.c: In function 'erase_effect':
| linux/drivers/input/ff-core.c:197: error: dereferencing pointer to incomplete type
| linux/drivers/input/ff-core.c:204: error: dereferencing pointer to incomplete type
| make[4]: *** [drivers/input/ff-core.o] Error 1

Argh! Sorry about it.

quoted

As the incomplete type is `struct task_struct', including <linux/sched.h> fixes
it.

Not linux/spinlock.h? I wonder if I need to include linux/spinlock.h and

Nope, tried that first...

quoted

linux/mutex.h directly from linux/input.h... What is the current
policy on headers - do they need to include everything to be
functional or it is responsibility of the user?

Theoretically it's the responsibility of the header to include 
everything it needs.

Indeed. But due to Include Hell that's not always possible.

In practice we are after -rc8 and even thinking of this kind of #include 
changes under include/linux/ makes me nervous - like the fact that the 
ff-core.c problem occured _only_ on m68k our headers are too fragile for 
expecting such changes to simply work.

Can we go with Geert's patch for 2.6.26 and if you want to fix it 
properly you can send a patch for 2.6.27?

And let the proper patch boil in linux-next for a while...

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds