lagg(4): LOR, deadlock and panic

[Matt Joras]

On Tue, 2016-06-14 at 09:26 -0600, Alan Somers wrote:
> 
> I don't know the best answer either.  But while you're in there, are
> you interested in fixing any other lagg panics too?  I've written
> some
> ATF torture tests for lagg, but I haven't checked them into head yet
> because most of them quickly panic.
> 
> -Alan
We run into if_lagg and if_vlan panics at $WORK all the time in our
automation. I've fixed the if_vlan panics and I'm hoping to update this
review: https://reviews.freebsd.org/D5825 soon with something that
accomodates drivers sleeping in the vlan_*config event handlers (which
involves having a global rmlock _and_ sx in if_vlan).

I was planning on doing a similar audit/fixing of if_lagg soon when I
get the chance.

Matt Joras