Hello Krzysztof,

On 07/05/2016 02:33 AM, Krzysztof Kozlowski wrote:

On 07/04/2016 05:15 PM, Javier Martinez Canillas wrote:

[snip]

quoted

Yes, splitting the lock per controller will fix the possible deadlock in
this case but I think we need an approach that is safe for all possible
scenarios. Otherwise it will work more by coincidence than due a design.

This is not a coincidence. This design is meant to fix this deadlock.
Not by coincidence. By design.

Ok, if the configurations I described doesn't exist in practice and are
just theoretical then yes, doing a per controller lock is a good design. 
 

You are talking about theoretical different configurations... without
even real bug reports. I am providing an idea to fix a real deadlock and
your argument is that it might not fix other (non-reported) deadlocks.
These other deadlocks happen now as well probably...

I'm not against you re-working the locks to do it per controller, is just
that I thought it would be good to have a solution that is going to work
for all possible scenarios.

You asked for comments/opinions/ideas and I gave mine, that's all :)

Best regards,
Krzysztof

Best regards,
-- 
Javier Martinez Canillas
Open Source Group
Samsung Research America