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AMD silently removes memory encryption from consumer Ryzen CPUs

tomshardware.com

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Re: AMD silently removes memory encryption from consumer Ryzen CPUs

#131

Post by vel0city »

ChocolateGod wrote: post #95
embedding-shape wrote: post #49

Earlier quoted context omitted.

So reading between the lines, you're saying it's bad for AMD to disable undocumented features because people still might have bought them for those undocumented features, particularly for gaming servers?

I can't even think of what benefit memory encryption has for gaming servers?

IIRC, this memory encryption function can let a hypervisor tell the platform to use different encryption keys for different virtual machines. So even if somehow a compromised VM managed to read data from a neighboring VM theoretically they'd get garbled, encrypted data.

Re: AMD silently removes memory encryption from consumer Ryzen CPUs

#132

Post by mort96 »

izacus wrote: post #128
mort96 wrote: post #123

Earlier quoted context omitted.

There's plenty of features in products I buy which aren't "marketed", which I nonetheless get upset if are suddenly removed.

[flagged]

A great example of a non-sequitur. I will interpret this to mean you concede and are not interested in continuing this conversation.

Re: AMD silently removes memory encryption from consumer Ryzen CPUs

#133

Post by baq »

mystraline wrote: post #102
throw0101c wrote: post #93

Earlier quoted context omitted.

From a few years ago: > Five guys moving a server to a new datacenter without shutting it down. Without cutting it off from the internet. And as using a car would have been too easy, they used public transport. * https://www.youtube.com/watch?v=vQ5MA685ApE (DE audio, EN subs) See also perhaps: > The HotPlug allows hot seizure and removal of computers from the field to anywhere else. The HotPlug's patented technology…

Thats rough. If anything, thats an indication to me to make a HA setup so you can power down 1 member. Im not going to watch a video, honestly, but HA with a front-facing Zookeeper and sharded Postgres isnt super hard. Can be if you didnt initially plan for it. Ideally, you need an odd amount of quorum machines to properly handle split brain decisions... But if its a money issue, you can technically get by with just…

You are not the market.

> We created this product for our Government/Forensic customers

Re: AMD silently removes memory encryption from consumer Ryzen CPUs

#134

Post by marklubi »

throw0101c wrote: post #93
DanielHB wrote: post #41

Earlier quoted context omitted.

Reminds me of that Seinfeld episode where George tries to move a Frogger arcade machine without powering it off in order to not lose his high score leaderboard. https://youtu.be/5etwHVarNgI?t=256

From a few years ago: > Five guys moving a server to a new datacenter without shutting it down. Without cutting it off from the internet. And as using a car would have been too easy, they used public transport. * https://www.youtube.com/watch?v=vQ5MA685ApE (DE audio, EN subs) See also perhaps: > The HotPlug allows hot seizure and removal of computers from the field to anywhere else. The HotPlug's patented technology…

Thanks for sharing the video of moving the server.

I wouldn't say that I miss those days, but there's some good nostalgia there having done some things that feel pretty similar (early 2000s). Not quite to that extreme though.

Re: AMD silently removes memory encryption from consumer Ryzen CPUs

#135

Post by iamnothere »

deno wrote: post #130
linkgoron wrote: post #127

Earlier quoted context omitted.

What are you trying to prove? He never said you're wrong, just the fact that something is illegal doesn't mean that it won't happen to you, just that it's illegal - those are just words written in a book somewhere. Even so-called law bound adversaries break the law all the time. A cop beating you senseless or breaking into your home is illegal, but it happens all the time. You're welcome to sue after the fact.

This is not relevant to memory encryption, after all the police could just plant any false evidence. You use video camera/CCTV and other evidence gathering to document such illegal police action. Suing after the fact is a valid strategy and in free countries this would allow you to exclude illegally obtained evidence or evidence lacking proper chain of custody.

If you sue them they will just beat you with a wrench again. Courts are imaginary. You should stop resisting. /s

Re: AMD silently removes memory encryption from consumer Ryzen CPUs

#136

Post by andsoitis »

mort96 wrote: post #132
izacus wrote: post #128

Earlier quoted context omitted.

[flagged]

A great example of a non-sequitur. I will interpret this to mean you concede and are not interested in continuing this conversation.

Why are you upset about the removal of this particular “feature”?

Re: AMD silently removes memory encryption from consumer Ryzen CPUs

#137

Post by IshKebab »

bonzini wrote: post #47
riobard wrote: post #38

Earlier quoted context omitted.

Are you sure? I thought it's just AES without any authentication.

Yes, it's AES with a tweak based on the physical address. It adds some protection from RowHammer and the like because flipping a bit in encrypted memory is catastrophic, while it can be done in a controlled manner if it's not encrypted.

Surely ECC already does that. You don't need encryption.

Re: AMD silently removes memory encryption from consumer Ryzen CPUs

#138

Post by zamadatix »

alberth wrote: post #125
zamadatix wrote: post #106

Earlier quoted context omitted.

No clear difference beyond the scaling to 6x the memory channels, 24x the memory capacity, 12x the core count, 6x the PCIe lanes, and ability to double (or nearly double) these with a 2nd socket. There are also a few features, like per VM memory encryption, which have only ever been on Epyc (and "real" Epyc, not just any Epyc branded consumer platforms). Like the article hits spot on right at the start, it has nothin…

What’s the different between these two: Consumer: https://www.amd.com/en/products/processors/desktops/ryzen/90... EPYC variant: https://www.amd.com/en/products/processors/server/epyc/4005-...

The Epyc 4585PX falls into the `(and "real" Epyc, not just any Epyc branded consumer platforms)` note. I.e. it is the same CPU as the AMD Ryzen 9 PRO 9965X3D, branded differently because it is certified against "server" branded motherboards instead of "standard" PC motherboards (same socket/chipset though, outside firmware validation the two are swappable). It carries none of the actual Epyc feature sets, just the PRO features, and the feature differences are therefore the same as any other PRO CPU.

Re: AMD silently removes memory encryption from consumer Ryzen CPUs

#139

Post by porridgeraisin »

vel0city wrote: post #131
ChocolateGod wrote: post #95

Earlier quoted context omitted.

I can't even think of what benefit memory encryption has for gaming servers?

IIRC, this memory encryption function can let a hypervisor tell the platform to use different encryption keys for different virtual machines. So even if somehow a compromised VM managed to read data from a neighboring VM theoretically they'd get garbled, encrypted data.

That is not in this one. That is only the datacenter one(SEV) This one (SME) is a single machine wide key and it doesn't have integrity protection either.

Re: AMD silently removes memory encryption from consumer Ryzen CPUs

#140

Post by kouteiheika »

bob1029 wrote: post #96
functionmouse wrote: post #69

Earlier quoted context omitted.

it's exactly why we're not allowed a competitive market for CPUs we could all be burning our own tiny ~300nm feature size ICs at home for around the price of a blu ray burner and a dark room setup. Our silicon limitations are not for a lack of hardware, but rather a lack of freedom.

> a lack of freedom > ~300nm feature size Can you point to a specific regulation that prevents me from crafting shitty semiconductors in my shed? I am pretty sure there are entire YouTube channels dedicated to this.

> I am pretty sure there are entire YouTube channels dedicated to this.

There is: https://www.youtube.com/@Dr.Semiconductor

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