Re: [PATCH] lib: devres: add a comment about the devm_of_iomap() function

[Arnd Bergmann]

On Tue, Jun 9, 2020 at 12:47 PM Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote:
>
> We recently introduced a bug when we tried to convert of_iomap() to
> devm_of_iomap().  The problem was that there were two drivers mapping
> the same io region.  The first driver was using of_iomap() and the
> second driver was using devm_of_iomap() and the kernel booted fine.
> When we converted the first drive to use devm_of_iomap() then the second
> driver failed with -EBUSY and the kernel couldn't boot.
>
> Let's add a comment to prevent this sort of mistake in the future.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

Good idea,

Acked-by: Arnd Bergmann <arnd@xxxxxxxx>