- Panic immediately if witness says we're holding non-sleepable locks.
This helps ensure that we don't recurse on the pmap lock in
pmap_fault_fixup().
- Panic if the kernel faults on a user address without setting an
onfault handler.
- Panic if the fault occurred in a critical section or interrupt
handler, like we do on other platforms.
- Fix some style issues in trap_pfault().
Reviewed by: jhb
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18561
3ec68206f5