Re: [RFC] Remove or convert empty ioctls ?

From: Ingo Molnar
Date: Thu Oct 15 2009 - 11:52:03 EST



* Jeff Garzik <jeff@xxxxxxxxxx> wrote:

> On 10/15/2009 11:31 AM, Alan Cox wrote:
>> EINVAL means you used an ioctl that is correct for the driver but that
>> for some reason the driver didn't like it.
>
> Precisely.
>
> The driver author proactively chose to implement the ioctl and return
> a value other than ENOTTY.
>
> It is invalid to assume that all such cases are a direct result of
> author mistakes or ignorance.

If 10% of the cases the error return was for a reason it's still worth
doing this. If it matters we'll hear about it.

Something that looks like crap should not get extra protection to stay
in the kernel just because it 'might' be non-crap. If it's not clearly
documented in the source to be -EINVAL for a good reason (and frankly i
cannot think of any) then i'd suggest to do what Alan has been doing for
years: just change it and see if it causes any problems.

It's not like it's hard to revert such a change. (and we'll also add a
comment explaining the reason for the -EINVAL in that case.)

Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/