An addressing exception can also be detected while handling a TLB miss--if there is no page table entry assigned for the desired address, that address is not part of the address space of the processs.
When a user-mode process caused the addressing exception, the kernel sends the process a SIGSEGV (see the signal(5) reference page), usually causing a segmentation fault. When kernel-level code such as a device driver caused the addressing exception, the kernel executes a "panic," taking a crash dump and shutting down the system.