Linux 3.16: all my drivers on SPI bus report WARNING: at drivers/base/dd.c:286

[Stijn Devriendt]

On Thu, Aug 28, 2014 at 5:53 PM, leroy christophe
<christophe.leroy at c-s.fr> wrote:
>
> I've been able to identify the origin of the issue. It happens since the below commit.
> Do you know what should be done to fix that ?
>
> Christophe
>
>

Actually, more things are wrong with what the driver is doing.
If inside spi_add_device() the call to device_add() fails, then that
code bails out without any call to spi_cleanup() and the same
memory will leak (Is this intended?).

Basically, fsl_spi_setup allocates memory using devm_kzalloc, while
device_add expects that any memory allocated via this way is only
done in the device's probe function.

The simple fix would be to do a normal allocation (revert the patch) and
add a free to the cleanup() function. Unfortunately that doesn't fix the
memleak I mentioned above.

So, some outside-the-box thinking brings me to conclude that another way
to fix this problem is to allocate the devm_kzalloc not on the device's
resource
list but on the controller's resources (it's controller state after all...).

Regards,
Stijn