Re: [PATCH RFC] i2c algo, Add i2c-algo-i801 driver [v1]

[Prarit Bhargava <prarit-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

On 04/09/2014 01:37 PM, Matthew Garrett wrote:
> On Wed, 2014-04-09 at 13:34 -0400, Prarit Bhargava wrote:
>> On 04/09/2014 01:09 PM, Matthew Garrett wrote:
>>> Imagine an i2c chip with indexed register access. What stops:
>>>
>>> CPU0 (i2c):		CPU1 (ACPI):
>>> SBWB register address
>>> 			SBWB register address
>>> SBRB register value
>>> 			SBRB register value
>>>
>>
>> Your example is no different from what we've told people to do right now when
>> they see the ACPI resource conflict message and use a kernel parameter to
>> override the error condition.  I'm not disputing that this could be a problem --
>> see my previous comment about hoping that someone @ Intel will let us know if
>> we're doing something horrible.
> 
> Right. It's dangerous, which is why we forbid it by default. How do we
> benefit from having a driver that's no safer?

We have yet to see where the existing case exhibits the behaviour of a race.  In
fact, AFAICT, all we've seen is stability.  So it's no safer?  Yep.  It's as
equally not racy as the existing workaround.

P.

>