Print more useful information about the transfer that trigger the assertion.
Other data is available with ddb command 'show pginfo'.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Reset function on SandyBridge holds the gt_lock for the whole duration
already.  Also, according to the specs, GDRST register is not in the
power well, so the forcewake for reset status read is excessive for
this reason.

Use plain register read for waiting of the reset completion
notification, to avoid gt_lock recursion.  Linux upstream did the
similar change, but their code was already restructured.

Reported by:	ray
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Add a resource limit for the total number of kqueues available to the
user.  Kqueue now saves the ucred of the allocating thread, to
correctly decrement the counter on close.

Under some specific and not real-world use scenario for kqueue, it is
possible for the kqueues to consume memory proportional to the square
of the number of the filedescriptors available to the process.  Limit
allows administrator to prevent the abuse.

This is kernel-mode side of the change, with the user-mode enabling
commit following.

Reported and tested by:	pho
Discussed with:	jmg
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
Add a resource limit for the total number of kqueues available to the
user.  Kqueue now saves the ucred of the allocating thread, to
correctly decrement the counter on close.

Under some specific and not real-world use scenario for kqueue, it is
possible for the kqueues to consume memory proportional to the square
of the number of the filedescriptors available to the process.  Limit
allows administrator to prevent the abuse.

This is kernel-mode side of the change, with the user-mode enabling
commit following.

Reported and tested by:	pho
Discussed with:	jmg
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks