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Comment by cptskippy | Hacker News Reader

How would an open source processor be better from a security perspective? I might still be a little shell shocked from my attempts to setup a MythTV Box 10 years ago but this is what's running through my head:

"Did you RTFM?"

"Debain CPU doesn't have that issue."

"Just disable the ALUs in firmware, they're not necessary in modern processors anyways."

"That's been patched, just download processor v2.3.4.432 and send it to your FAB, they should spin you a new CPU in 8-12 months."

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While the comparison to MythTV for a fun coment, this is exactly what ARM would like the high level decision makers to feel. Just as Microsoft tried with their "get the facts" campaign years ago.

Notwithstanding your terrible MythTV experience, there's seveal companies offering commercial support for Linux today, and a lot of effort has been put into making it as secure as the Windows equivalent. I suspect the same could happen with RISC-V.

Another comment mentioned Western Digital switching to RISC-V which makes a lot of sense and that's about it. I'm struggling to see how RISC-V would improve the situation with edge devices or personal computing devices where the implementations will probably end up being propriety in nature and beholden to the vendor for any updates.

Even when we do get something like a custom ROM for a router or smartphone it will still be reliant on custom kernel modules or other lock-ins hindering open source support.

It just feels like more of the same with a chance for ODMs to save some on the BOM while not passing the savings on to us.

I guess it's just hard to get excited about it without seeing some sort of benefit to the end user. That doesn't mean I feel like we should stick with ARM or x86, I frankly don't care.

All of that sounds better than: "Oh, our new processors don't have that issue. Trust us, pay me. Oh, you just bought one? Too bad."

It sounds about the same.

yes, it does.

Some open source projects are different. A lot of them do not cater to end users directly. But if you want to talk about open source security, take a look at how OpenBSD handles issues; they definitely aren't messing around.

That's all true, I'm just wondering how things would be different if everyone were using an Open Source CPU vs what we have today.

If everyone is running the same CPU design but sourced from different manufacturers who had them spun up at different fabs, how would that affect support? Today we have one or two device manufacturers we rely on for support and answers about if security fixes can be done in firmware vs requiring a hardware fix. We can pull the CPU ID of our system and then check with AMD or Intel for an authoritative answer. What does that look like when anyone can manufacture a chip?

Will there still end up being one or two predominant CPU manufactures for desktop/mobile/server CPUs to simplify support? Are we going to have to rely on OEMs to support the CPUs they put in their machines?

I'm fearful we might end up in a situation similar or worse to what we have with Android where smartphones are shipped in their final state and never receive anything beyond failure support from the OEM/ODM.

That's the case today: ARM CPUs are sourced from different manufacturers and packaged together with other cores into SoCs, which have wildly varying support from their vendors. Some of these processors also have custom extensions. If you're worried about chip security when anyone can manufacture a chip, then sorry, we're already there, and RISC-V doesn't change that.

So what does it solve that's a problem today?

* Serious question. Apart from the freedom and control aspects of the Open Source model, what is solved with an open source CPU architecture or what are the benefits?

I can see being able to spin your own chips would enable an OEM/ODM to keep producing the same old design indefinitely where as reliance on Intel/AMD/Samsung/Mediatek means you have to refresh your design. That could be both a benefit and a detriment depending on how you look at it.

Again, being able to spin your own chips isn't really at issue here, that's already possible. ARM and MIPS will likely happily let you continue to make chips based on old cores as long as you continue to pay your license fees.

The freedoms from the Open Source model is substantial enough to make it attractive on that basis alone, just as for Linux/BSD. One example is Western Digital transitioning to RISC-V for their hard drive controllers. I would imagine being able to add your own instructions without having to deal with NDAs and non competes with ARM will be attractive to a lot of OEMs.

Just like with Linux, it's difficult to anticipate what intersting things will come out of RISC-V, but one interesting example is a formally verified RISC-V core, picorv32: https://github.com/cliffordwolf/riscv-formal/tree/master/cor... (presentation here: https://www.youtube.com/watch?v=VU97ffHF_IQ). According to the author, this core will power safety critical applications at a synchrotron: https://theamphour.com/374-an-interview-with-clifford-wolf/

Note that RISC-V is _not_ an open-source processor, but an open-source instruction set architecture.

Which means that anyone can implement the instruction set and thus many different implementations can be made. Most likely there will not be one common and shared processor.

I have been wondering, how far are we from a simple but powerful enough open source RISC-V CPU running OpenBSD in our Router or some Network Appliance.

You might want to have a look at lowRISC. https://www.lowrisc.org

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