De-virtualize V_pf_mtag_z to eliminate kernel panics.

[Marko Zec]

On Saturday 27 July 2013 16:48:00 Adrian Chadd wrote:
> I'm happy keeping it virtual (it lets us do things like set per-vimage
> mbuf tag limits, and having per-vimage mbufs may be a useful long term
> stretch goal to have).. we just have to think about this stuff in more
> detail.

The V_pf_mtag_z zone apparently doesn't have any size limits, so it doesn't 
enforce mbuf tag limits in pf, and certainly it doesn't enforce any limits 
outside of PF?

And while otherwise I wouldn't terribly object to keep V_pf_mtag_z virtual, 
if we don't de-virtualize it, would you have an alternative proposal to 
resolve the panics in PF which Craig wants to have fixed?

Finally, while the idea about enforcing per-vnet mbuf (and tag) limits may 
look neat on the surface, the fact that mbufs may flow freely between vnets 
makes this idea less trivial to implement than it may appear at the first 
glance.  In any case, IMO that issue is entirely unrelated to the patch 
Craig proposed, and should be discussed separately.

Marko