Re: 2.6.36/2.6.37: broken compatibility with userspace input-utils?

From: Mark Lord
Date: Tue Jan 25 2011 - 09:28:31 EST


On 11-01-25 12:29 AM, Dmitry Torokhov wrote:
> On Tue, Jan 25, 2011 at 12:04:10AM -0500, Mark Lord wrote:
>> On 11-01-24 11:55 PM, Dmitry Torokhov wrote:
>>> On Mon, Jan 24, 2011 at 11:37:06PM -0500, Mark Lord wrote:
..
>>> The options are:
>>>
>>> 1. Convert to EVIOCGKEYCODE2
>>> 2. Ignore errors from EVIOCGKEYCODE and go through all 65536 iterations.
>>
>> or 3. Revert/fix the in-kernel regression.
>>
>> The EVIOCGKEYCODE ioctl is supposed to return KEY_RESERVED for unmapped
>> (but value) keycodes, and only return -EINVAL when the keycode itself
>> is out of range.
>
> You are inventing rules. You are requesting a scancode->keycode
> mapping. If scancode is unknown/invalid for the device ioctl returns
> -EINVAL.

-EINVAL signals bad/invalid parameters.
That's NOT what is happening here.

> For unmapped - yes, either KEY_RESERVED or KEY_UNKNOWN should be
> returned. For invalid scancodes -EINVAL shoudl be returned.

Exactly my point. The scancode in question is 100% valid and mapable,
yet the kernel is rejecting it as -EINVAL. Incorrect.

BUG. Regression. Breaks userspace. Must get fixed.

Cheers
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