Re: Sed-opal fixups

[Jens Axboe]

On 02/09/2017 10:45 AM, Scott Bauer wrote:
> On Thu, Feb 09, 2017 at 05:43:20PM +0000, David Laight wrote:
>> From: Scott Bauer
>>> Sent: 09 February 2017 17:20
>>> It may be too late to change anyhting in the uapi header. When we
>>> switched over to using IOC_SIZE I found a bug where I had switched
>>> up a structure in one of the series from v4 to v5 but never changed
>>> the structure in the IOW. The structure that was in there was to small
>>> so when we kzalloc on it we don't request enough space. It worked before
>>> because we were using the cmd strictly as a command #, not using the IOC
>>> and friends.
>>>
>>> If it's too late to modify that IOW, I can work around it by reallocing
>>> on the correct size for that command only. I verified the rest of the
>>> commands and the structures are the same.
>>>
>>> Let me know what you think, please.
>>
>> Maybe define IOC_OPAL_ACTIVATE_LSP_OLD to the incorrect value and
>> IOC_OPAL_ACTIVATE_LSP to the correct one.
>> But that relies on any users specifying the correct structure.
>> I wouldn't guarantee that.
> 
> I think I'm the only userspace user right now, this went in on monday,
> so I can can change my tooling easily. I just wasnt sure if there was a
> set time where the user ABI cannot be changed.

We can still change it, and we definitely should if it improves the
interface. It's not a ABI until it's in a released, final kernel.

-- 
Jens Axboe