Xscale was Intel prior to a 2006 sale to Marvell. Best regards, Rick C. Hodgin
-------- Original Message -------- From: Wookey <[email protected]> Sent: Thu, Jun 28, 2012 02:39 PM To: [email protected] CC: Subject: Re: [Freedombox-discuss] Backdoor in military chips may also be in Freedombox >+++ [email protected] [2012-06-28 12:30 -0400]: >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA1 >> >> I am requested that Freedombox >> ask ARM and Marvell if there is a debugger, ARM's TrustZone, >> antitheft and a visible PSN. > >xscale CPUs have a debug facility, consisting of 32K of sram which is >enabled in debug state allowing the CPU state to be interrogated >without affecting anything else about what is going on. This has been >documented in the xscale docs since they were released circa 2003. So >do other ARM CPUs, although manufacturer's implementations vary. I >believe all current CortexA series CPUs have Trustzone, but I could be >wrong. PSN processor serial number? xscales have an ID and chip >stepping. They don't have a unique serial number SFAIK. Embedding the >variation needed for serial numbers into chips is difficult so is not >normally done, but I haven't been taking much notice of hardware >details since xscale. > >However the existence of these things is not the same as them being >any meaningful sort of threat. It depends on many things, like how the >SOC is connected up and exactly what the CPU's hardware capability is. >In general I'd bne a lot more worried about code running on the CPU in >the normal way than code accessing the debug and trustzone modes, but >those are obviously worth checking for vulnerabilities. If you succeed >in hacking trustzone you can probably make actual real money :-) > >Wookey >-- >Principal hats: Linaro, Emdebian, Wookware, Balloonboard, ARM >http://wookware.org/ > >_______________________________________________ >Freedombox-discuss mailing list >[email protected] >http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/freedombox-discuss _______________________________________________ Freedombox-discuss mailing list [email protected] http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/freedombox-discuss
