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. > -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
