Re: [PATCH 1/2] libsas: Don't process sas events in static works

From: John Garry
Date: Mon May 22 2017 - 05:28:59 EST

On 22/05/2017 06:54, wangyijing wrote:
I also think for safety this should use a mempool that guarantees that
> events can continue to be processed under system memory pressure.
What I am worried about is it's would still fail if the mempool is used empty during memory pressure.

> Also, have you considered the case when a broken phy starts throwing a
> constant stream of events? Is there a point at which libsas should
> stop queuing events and disable the phy?
Not yet, I didn't find this issue in real case, but I agree, it's really a problem in some broken
hardware, I think it's not a easy problem, we could improve it step by step.


I have seen this scenario on our development board when we have a bad physical cable connection - the PHY continually goes up and down in a loop.

So, in this regard, it is worth safeguarding against this scenario.