tree 391bbee989a6ab6ab22d7b4b32a0b7850602d5be
parent 64bedffe496820dbb6b53302d80dd0f04db33d8e
author James Hogan <james.hogan@imgtec.com> 1423238637 +0000
committer James Hogan <james.hogan@imgtec.com> 1427491507 +0000

MIPS: KVM: Handle TRAP exceptions from guest kernel

Trap instructions are used by Linux to implement BUG_ON(), however KVM
doesn't pass trap exceptions on to the guest if they occur in guest
kernel mode, instead triggering an internal error "Exception Code: 13,
not yet handled". The guest kernel then doesn't get a chance to print
the usual BUG message and stack trace.

Implement handling of the trap exception so that it gets passed to the
guest and the user is left with a more useful log message.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org