[OpenAFS-devel] Re: Cache corruption with RX busy code

[chas williams - CONTRACTOR]

On Thu, 18 Apr 2013 10:52:24 -0500
Andrew Deason <adeason@sinenomine.net> wrote:

> On Thu, 18 Apr 2013 07:49:28 -0400
> chas williams - CONTRACTOR <chas@cmf.nrl.navy.mil> wrote:
> 
> > > I'm not looking at the code at the moment, but don't we get the serial
> > > of the offending packet in the BUSY we receive? Therefore, we should be
> > > able to ignore a BUSY packet if it does not reference the most recent
> > > serial we've sent.
> > 
> > Even if we did, I think that a race between two new connections would
> > both have the same starting serial number (even if the starting serial
> > numbers were random, it would just make the problem more unlikely but
> > still possible).
> 
> We have the CID and epoch, too. I meant all of that in the context of
> the relevant connection, which we can identify.

I don't think the client is sent back its own epoch, but rather the
epoch for the server.   And I still believe a connection id collision
is possible, but yes, very unlikely.