[Cryptography] [Crypto-practicum] Secure erasure in C.

Henry Baker hbaker1 at pipeline.com
Wed Sep 7 20:09:02 EDT 2016

At 04:18 PM 9/7/2016, Harlan Lieberman-Berg wrote:
>If you really want to be sure it's dead and buried, what about doing the erasure with inline asm?  I know GCC, at least, has a keyword to tell it not to mess with a particular assembly block.

nVidia's "Dynamic Code Optimization" (DCO) means you can no longer trust assembler code, either, since DCO has replaced a rigorous semantics with a simple "hint" (DWIM -- "Do What I Mean", not what I say; but who knows what you mean?)

Here's more about DCO:

"DCO": Yet more lovely places for malware to hide.  The executing code is "translated" into a microcode buffer, but who gets to be in charge of said translation?

"Those who cast the votes decide nothing.  Those who count the votes decide everything."  -- Josef Stalin

I believe that these DCO processors have already been picked up for widespread use in automobiles, including self-driving cars.

What, me worry?


Stanford EE Computer Systems Colloquium
4:15PM, Wednesday, March 4, 2015
NEC Auditorium, Gates Computer Science Building Room B3

Dynamic Code Optimization and the NVIDIA Denver Processor

Nathan Tuck NVIDIA

About the talk:

NVIDIA's first 64-bit ARM processor, code-named Denver, leverages a host of new technologies to enable high-performance mobile computing.  Implemented in a 28-nm process, the Denver CPU can attain clock speeds of up to 2.5 GHz.  This talk will outline the Denver architecture and describe some of its technological innovations.  In particular this talk will discuss some of the motivations and advantages of dynamic code optimization.


There not downloadable slides for this presentation available at this time.


View Video on YouTube.


About the speaker:

Nathan Tuck has been a member of the DCO and CPU architecture teams at NVIDIA since 2009.

Nathan has spent his professional career walking a crooked line between hardware and software.  As an engineer, he is most interested in working on systems problems.  Professionally, he is most interested in dynamic environments where he can make a large difference.

Contact information:

Nathan Tuck

More information about the cryptography mailing list