http://www.theregister.co.uk/2010/11/15/amd_secret_debugger/ By Dan Goodin in San Francisco The Register 15th November 2010 A hardware hacker has discovered a secret debugging feature hidden in all AMD chips made in the past decade. The password-protected debugger came as a shock to reverse-engineers who have hungered for an on-chip mechanism for performing conditional and direct-hardware breakpoint operations. Although AMD has built the firmware-controlled feature into all chips since the Athlon XP, the company kept it a closely guarded secret that was only disclosed late last week by a hacker who goes by the name Czernobyl. “AMD processors (Athlon XP and better) have included firmware-based debugging features that expand greatly over standard, architecturally defined capabilities of x86,” the hacker wrote. “For some reason, though, AMD has been tightly secretive about these features; hint of their existence was gained by glancing at CBID's page.” To put a chip into developer mode, a user must first enter what amounts to a password -- 9C5A203A -- into the CPU's EDI register. Czernobyl was able to deduce the secret setting by brute forcing the key. [...] ___________________________________________________________ Tegatai Managed Colocation: Four Provider Blended Tier-1 Bandwidth, Fortinet Universal Threat Management, Natural Disaster Avoidance, Always-On Power Delivery Network, Cisco Switches, SAS 70 Type II Datacenter. Find peace of mind, Defend your Critical Infrastructure. http://www.tegataiphoenix.com/Received on Mon Nov 15 2010 - 22:13:25 PST
This archive was generated by hypermail 2.2.0 : Mon Nov 15 2010 - 22:21:56 PST