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Can you reverse engineer an ASIC?

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Re: Can you reverse engineer an ASIC?

#61

Post by Joel_Mckay »

perching_aix wrote: post #37
Joel_Mckay wrote: post #27

Earlier quoted context omitted.

I’d recommend the Chenming-Hu books on solar cells and semis available as pdfs on his site. https://www.chu.berkeley.edu/modern-semiconductor-devices-fo... LLMs have already been shown to cause cognitive/skill performance losses in some users. =3 https://www.youtube.com/watch?v=axOcn--n_lM

> LLMs have already been shown to cause cognitive/skill performance losses in some users. =3 Sorry to interrupt your smugness, but have you actually read that study? It's basically tautological: people remained mostly unfamiliar with code they did not write, and remained mostly unfamiliar with a library they did not use. That's kind of the whole point to begin with! https://homepages.inf.ed.ac.uk/rni/papers/realprg.h…

Quod erat demonstrandum =3

Re: Can you reverse engineer an ASIC?

#62

Post by perching_aix »

Joel_Mckay wrote: post #61
perching_aix wrote: post #37

Earlier quoted context omitted.

> LLMs have already been shown to cause cognitive/skill performance losses in some users. =3 Sorry to interrupt your smugness, but have you actually read that study? It's basically tautological: people remained mostly unfamiliar with code they did not write, and remained mostly unfamiliar with a library they did not use. That's kind of the whole point to begin with! https://homepages.inf.ed.ac.uk/rni/papers/realprg.h…

Quod erat demonstrandum =3

I genuinely wish you were at least half as smart as you think you are, cause then you wouldn't be acting obnoxiously like this, willfully betraying your own values.

It'd be generally awesome if the last bastions of humanity actually demonstrated any of the values they're championing so hard at all.

Re: Can you reverse engineer an ASIC?

#63

Post by i_am_a_peasant »

MomsAVoxell wrote: post #58
Aurornis wrote: post #32

Earlier quoted context omitted.

> He did that by connecting oscyloscops to all chip's outputs and started with applying random current on inputs This is absolutely not how reverse engineering a digital logic ASIC works. Either the story got embellished through retellings, or this person was a fantasist. There are people who hack on GPUs but it’s done at the software level. I did get a kick out of imagining a scene where someone is trying to connect…

Many laymen confuse logic analyzers with oscilloscopes. Don't take it personally - the person you responded to is clearly not a native English speaker. You absolutely can reverse chips with logic analysis. It is big business in some parts of the world.

with very, very expensive logic analyzers... But yeah, nothing weird here. Plus OP was retelling a story of someone else doing it, while probably not being a specialist in this field. So I wouldn't take the "random inputs" part literally.

Re: Can you reverse engineer an ASIC?

#64

Post by i_am_a_peasant »

pixelatedindex wrote: post #24
zie1ony wrote: post #6

At my uni, 15 years ago, one postdoc reverse engineered NVIDIA chip and wrote more performant compiler. He did that by connecting oscyloscops to all chip's outputs and started with applying random current on inputs. Using ML and his genius he rediscoverd all opcodes including a few hidden ones. Eventually he got hired by some company that was doing a lot of GPU on supercomputers.

“oscyloscops” is a way better spelling I gotta say.

sounds like a mythical creature hahaha

Re: Can you reverse engineer an ASIC?

#65

Post by inigyou »

JSR_FDED wrote: post #45
inigyou wrote: post #8

Earlier quoted context omitted.

You can't do that by applying random inputs to any single-chip GPU - it has far too much state. I can see that perhaps it worked on some of the early multi-chip cards - where one chip was a texture sampler, and so on. You'll have more luck reverse engineering the software driver first. They're not hidden, you can just open the driver files in Ghidra, the almost-universal tool for open-sourcing proprietary code. Hidde…

Small pedantic nit: Open-sourcing is not the same as reverse-engineering.

We are taking back control of our computers by force.

Re: Can you reverse engineer an ASIC?

#67

Post by Joel_Mckay »

perching_aix wrote: post #62
Joel_Mckay wrote: post #61

Earlier quoted context omitted.

Quod erat demonstrandum =3

I genuinely wish you were at least half as smart as you think you are, cause then you wouldn't be acting obnoxiously like this, willfully betraying your own values. It'd be generally awesome if the last bastions of humanity actually demonstrated any of the values they're championing so hard at all.

I would never kink shame a persons cognitive dildo, or irrational off-topic cult dogma.

Have a wonderful day =3

Re: Can you reverse engineer an ASIC?

#68

Post by perching_aix »

Joel_Mckay wrote: post #67
perching_aix wrote: post #62

Earlier quoted context omitted.

I genuinely wish you were at least half as smart as you think you are, cause then you wouldn't be acting obnoxiously like this, willfully betraying your own values. It'd be generally awesome if the last bastions of humanity actually demonstrated any of the values they're championing so hard at all.

I would never kink shame a persons cognitive dildo, or irrational off-topic cult dogma. Have a wonderful day =3

[dead]

Re: Can you reverse engineer an ASIC?

#69

Post by Aurornis »

MomsAVoxell wrote: post #58
Aurornis wrote: post #32

Earlier quoted context omitted.

> He did that by connecting oscyloscops to all chip's outputs and started with applying random current on inputs This is absolutely not how reverse engineering a digital logic ASIC works. Either the story got embellished through retellings, or this person was a fantasist. There are people who hack on GPUs but it’s done at the software level. I did get a kick out of imagining a scene where someone is trying to connect…

Many laymen confuse logic analyzers with oscilloscopes. Don't take it personally - the person you responded to is clearly not a native English speaker. You absolutely can reverse chips with logic analysis. It is big business in some parts of the world.

> You absolutely can reverse chips with logic analysis.

You are not going to reverse engineer a GPU with a logic analyzer and by applying currents to pins.

You could replace oscilloscope with logic analyzer in the comment above and nothing changes. It’s a fantasy story. The GPU I/O is high speed PCIe and memory buses.

If you want to explore the chip you connect it to a PCIe host and use the host. Connecting logic analyzers and applying current to pins does not make sense on any level.

Also, if you think probing high speed signals like PCIe or memory buses with logic analyzers is easy, you’ve probably never tried it. The equipment needed to do that properly is incredibly expensive because even probing those buses slightly incorrectly or with cheap probes will make them fail to work at the speeds they use.

Re: Can you reverse engineer an ASIC?

#70

Post by Aurornis »

i_am_a_peasant wrote: post #63
MomsAVoxell wrote: post #58

Earlier quoted context omitted.

Many laymen confuse logic analyzers with oscilloscopes. Don't take it personally - the person you responded to is clearly not a native English speaker. You absolutely can reverse chips with logic analysis. It is big business in some parts of the world.

with very, very expensive logic analyzers... But yeah, nothing weird here. Plus OP was retelling a story of someone else doing it, while probably not being a specialist in this field. So I wouldn't take the "random inputs" part literally.

> with very, very expensive logic analyzers... But yeah, nothing weird here.

You can’t simply get an expensive logic analyzer and probe PCIe or memory buses at these speeds. There are expensive custom fixtures that need to be made to even begin to be able to probe at these speeds without disturbing the circuit so much that it fails to work. This isn’t like probing the I2C bus on a raspberry pi. It would be like connecting to the pins under the chip. It’s fantasy.

It’s also illogical. If you have a PCIe device, you plug it in to a PCIe host and use the host to interact with it. You don’t start probing pins and trying to apply signals to it.

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