Re: [PATCH 2/8] Input: ff-core - make use of __free() cleanup facility

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Fri, Dec 20, 2024 at 01:36:59PM +0100, Marek Szyprowski wrote:
> On 07.11.2024 08:15, Dmitry Torokhov wrote:
> > Annotate allocated memory with __free(kfree) to simplify the code and
> > make sure memory is released appropriately.
> >
> > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> > ---
> >   drivers/input/ff-core.c | 19 ++++++-------------
> >   1 file changed, 6 insertions(+), 13 deletions(-)
> 
> This patch landed in linux-next as commit 5203b3a18c1b ("Input: ff-core 
> - make use of __free() cleanup facility"). In my tests I found that it 
> causes the following kernel panic on some of my test boards. Reverting 
> it, together with fd5ba0501d38 ("Input: ff-memless - make use of 
> __free() cleanup facility") on top of next-20241220 fixes this panic 
> issue.

Gah, I fixed this once and then undid it for some reason. I think the
following should fix the problem:


diff --git a/drivers/input/ff-core.c b/drivers/input/ff-core.c
index a235d2eb6b31..c25e05eeb8e5 100644
--- a/drivers/input/ff-core.c
+++ b/drivers/input/ff-core.c
@@ -315,7 +315,6 @@ int input_ff_create(struct input_dev *dev, unsigned int max_effects)
 	ff->max_effects = max_effects;
 	mutex_init(&ff->mutex);
 
-	dev->ff = no_free_ptr(ff);
 	dev->flush = input_ff_flush;
 	dev->event = input_ff_event;
 	__set_bit(EV_FF, dev->evbit);
@@ -328,6 +327,7 @@ int input_ff_create(struct input_dev *dev, unsigned int max_effects)
 	if (test_bit(FF_PERIODIC, ff->ffbit))
 		__set_bit(FF_RUMBLE, dev->ffbit);
 
+	dev->ff = no_free_ptr(ff);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(input_ff_create);
diff --git a/drivers/input/ff-memless.c b/drivers/input/ff-memless.c
index 0bbeceb35545..e9120ba6bae0 100644
--- a/drivers/input/ff-memless.c
+++ b/drivers/input/ff-memless.c
@@ -524,7 +524,6 @@ int input_ff_create_memless(struct input_dev *dev, void *data,
 		return error;
 
 	ff = dev->ff;
-	ff->private = no_free_ptr(ml);
 	ff->upload = ml_ff_upload;
 	ff->playback = ml_ff_playback;
 	ff->set_gain = ml_ff_set_gain;
@@ -541,6 +540,8 @@ int input_ff_create_memless(struct input_dev *dev, void *data,
 	for (i = 0; i < FF_MEMLESS_EFFECTS; i++)
 		ml->states[i].effect = &ff->effects[i];
 
+	ff->private = no_free_ptr(ml);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(input_ff_create_memless);


Thanks.

-- 
Dmitry