78cb82148f
handling code so the stack trace unwinders don't start trying to go into user-space. Found by trying to create core dumps with a KTR_COMPILE/KTR_GEOM kernel, which results in a stack_save() call in the ast() coredump path - this created a panic, and then calling 'trace' in ddb resulted in the black screen of death after printing out most of the backtrace.