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New AMD side channel attacks discovered, impacts Zen architecture
- spectramax 7y agoI just wanted to say this about Intel vs AMD. Back when Intel was the "underdog" it couldn't compete with Athlon/Opeteron CPUs from AMD with its Pentium IV line, fan boys from both sides continually escalated the armchair warfare on Slashdot and Anandtech forums when Intel finally came out with the Conroe architecture that blew the competition away. I've seen this pendulum swing from one side to the other and back. Putting Intel marketing (awful) and AMD's marketing (awful again...), and their fan bases (toxic) aside, can we acknowledge the fact that working on a computer architecture is an extraordinarily complex task and that requires brilliant people all working together? I'll defer this fascinating topic, which most software engineers and tech enthusiasts are completely and utterly unaware of, to this talk by the legendary chip designer (x86 spec coauthor, A4/A5/Zen/Tesla AI ASIC architect) - Jim Keller and his interview with Lex Fridman: https://www.youtube.com/watch?v=Nb2tebYAaOA https://www.youtube.com/watch?v=Nb2tebYAaOA Designing & manufacturing computer chips is hard af, having worked in semiconductor manufacturing for over 12 years (primarily on the backend side of the Fab). Edit: Redacting some specifics
- t-writescode 7y agoOh yes, totally. I have complete respect for Intel’s engineers. It’s their business department I’ve long had trouble with, but those engineers do truly astonishing, near zero bug work.
- spectramax 7y agoI think the culture is improving despite of cashing it out in the 90's and 2000's during the Ballmer / Jack Welsch era. Semiconductor industry hasn't done a good job of cultivating a good, positive company culture and making it less regimented. We need to make it cool to work in a semiconductor company. I can assure you that there are so many incredible challenges that exist - with good definition/funding to tackle them from materials to marketing (direly needs to revamped). Imagine running a portion of the world's most advanced manufacturing processes. Ultra high volume (thousands of wafer starts per week), mind you. Perhaps videos such as these are shining a positive light on the entire semiconductor goodwill: https://www.youtube.com/watch?v=f0gMdGrVteI https://www.youtube.com/watch?v=f0gMdGrVteI
- aidos 7y agoWow. Those machines are something else altogether. I watched a chip making clip a while back and I recall that they talked about having to make strange patterns in the stencils (not sure what they’re called) to work around the way the light twists when it actually hits the die. I’ve probably got most of that wrong but is that still a thing with the addition of the water layer?
- spectramax 7y agoYeah, they calculate the transfer function of the pattern and then pattern the mask to achieve the end result printed on the silicon substrate. With EUV lithography, it substantially reduced this pattern complexity. Jim talks about it at this mark in this presentation: https://youtu.be/Qnl7--MvNAM?t=784 https://youtu.be/Qnl7--MvNAM?t=784
- saganus 7y agoSounds like this video: Indistinguishable from magic: Manufacturing modern computer chips https://youtu.be/NGFhc8R_uO4 https://youtu.be/NGFhc8R_uO4 Just amazing. I wish a newer video explaining more recent technologies was available.
- oarsinsync 7y ago> We need to make it cool to work in a semiconductor company. I'm not sure I agree. If by 'cool' you mean along the lines of receiving respect and admiration from others because, while they don't really understand the actual specifics of what you do, they have a general idea and it's celebrated widely, then I don't think we want that happening in semi space. It looks to me that it's happened already in software development, and I don't think the end result of that is net-positive. I think that when people are passionate about what they do, and do it because they're passionate about it, the end results tend to be better than if they're doing it because other people will give them recognition. I'm not saying this is something that happens all the time, and you can argue that I'm being elitest, snobby, or annoyed that the 'cool kids' have come into my playground and are playing with my toys, all of which would be valid positions to take. I do think that with all communities, they're very different when they have smaller appeal to when they have wider appeal. Niche communities are not without their problems (and the toxicity that can happen in them cannot be understated), but I personally prefer them, and believe the output is generally of a higher quality, than communities with wider appeal.
- Causality1 7y agoI think people also need to accept the fact we're never going to engineer a solution to human stupidity. If our society doesn't raise people to be good users, no amount of hardening will stop systems from being compromised.
- XMPPwocky 7y agoLike what? I've written in-depth about why "don't click untrusted links" is unhelpful: see https://xmppwocky.net/blog.py?page=22 https://xmppwocky.net/blog.py?page=22
- Nullabillity 7y agoThat domain isn't resolving.
- ZiiS 7y agoIt is also and untusted link, so I feel could only be preaching to the choir.
- Nullabillity 7y agoRight. Heh.
- gear54rus 7y agoAgreed. Wasting countless hours on the engineering end doesn't seem wise when those same hours could be spent doing something meaningful. This requires education on the user end. Education that will help them understand the world around them better so everyone wins in the end.
- pas 7y agoThose are wasted hours. We have to make stuff maximally safe AND educate users, because even that maximal safety/ergonomics/etc. is too little compared to how complex our world is.
- bdefore 7y agoReally enjoyed that video, all hour and a half of it. Thank you!
- ksec 7y agoI wouldn't use Underdog to describe Intel, they were never one in their x86 history. Always the TopDog. Intel in the P4 era is a lot different to now. P4 was an engineering mistake. And it wasn't Cornoe that saved that, it was Pat Gelsinger's Pentium M or Banias / Dothan. The current ( or past ) Intel issues isn't engineering, they have amazing engineers. It is lying. Blatant lies that were fed from Sales and Marketing all the way to their C-Level. That is what happen when a successful company were driven by Sales and Marketing people.
- acqq 7y ago> P4 was an engineering mistake. The story I've heard was that P4 was a management mistake. Some engineers claimed they surely understood that the limits existed, but the management believed that the only thing that's sellable is a bigger number of GHz. So the engineers got the goal to make a processor architecture for 10 GHz, and apparently P4 was made for that (long pipelines) and it was known that on lower number of GHz the architecture performed worse. But 10 GHz was unachievable because physics can't be cheated (the chips would simply melt without some special cooling that was also not sellable), so P4 architecture was never driven with the clock speeds for which it was designed.
- tuananh 7y agoAMD responds here https://www.amd.com/en/corporate/product-security https://www.amd.com/en/corporate/product-security > We are aware of a new white paper that claims potential security exploits in AMD CPUs, whereby a malicious actor could manipulate a cache-related feature to potentially transmit user data in an unintended way. The researchers then pair this data path with known and mitigated software or speculative execution side channel vulnerabilities. AMD believes these are not new speculation-based attacks. > AMD continues to recommend the following best practices to help mitigate against side-channel issues: > Keeping your operating system up-to-date by operating at the latest version revisions of platform software and firmware, which include existing mitigations for speculation-based vulnerabilities > Following secure coding methodologies Implementing the latest patched versions of critical libraries, including those susceptible to side channel attacks Utilizing safe computer practices and running antivirus software
- ItsTotallyOn 7y agoThis is legal/PR mumbo jumbo. Nowhere in that statement does AMD say they have patched this. instead, the make vague reference to previously-patched vulnerabilities that are NOT the vuln in question. Also, they say they 'believe' it isn't new, and that word is used for a reason - it isn't legally binding. It is a lot different than saying "It isn't new." Finally, the advice they give is akin to giving general advice for a Ford vehicle: "Change the oil every 3500 miles." Generalized statements that mean nothing. This looks to be an intentionally obfuscated response.
- altfredd 7y agoAMD does not "patch" Spectre. Spectre has to be patched by developers, who execute untrusted code within the trusted address space (e.g. browser and OS developers). I am taking AMD press release to mean, that this "attack" — note how researchers consistently use this word instead of "vulnerability" — is simply proof-of-concept for well known Spectre flaws or possibly even expected behavior of the CPU cache (in non-SMT case). Many Spectre-type flaws are essentially about an OS process reading/writing it's own memory — which it is naturally expected to have access to. Of course, browser developers weren't prepared for that, but they also were not prepared for gzip-bombs... I assume, that mitigations [1] suggested by AMD in 2018 are sufficient to protect against this (and all other) Spectre flavors on AMD CPUs, in which case there is really nothing new going on here. 1: https://developer.amd.com/wp-content/resources/90343-B_SoftwareTechniquesforManagingSpeculation_WP_7-18Update_FNL.pdf https://developer.amd.com/wp-content/resources/90343-B_Softw...
- Google234 7y agoIt’s interesting that the hundreds of AMD fans that seem to appear and gloat in every similar Intel thread aren’t present.
- npunt 7y agoUnderdog spirit
- hinkley 7y agoIt's best not to gloat about things we are all vulnerable to. My team at work has been snickering for two years about serious memory problems on a system our code partially replaces. I did not participate (see above). Guess what I've spent the last few weeks working on? Go ahead, guess.
- BoorishBears 7y agoI’ve said it before, half those people bought AMD stock, but are amateur Robinhood investors and didn’t diversify. So AMD vs Intel is very personal for them.
- trgfs85 7y ago>If you laugh at what other's don't have, you forget what you do. In general, AMD processors have fewer issues. Is that bad? Why bring others down instead of bring yourself up.
- Legogris 7y agoI'm quite certain that this is similarly to how there is little malware targeting Linux end-users. It's simply because Intel/Windows are the bigger platforms and therefore get more people looking at and targeting them.
- robdachshund 7y agoYeah I'm sure it has nothing to do with the fact that intels architecture is absolutely ancient
- 7y ago
- tylerl 7y agoI tried to read this 4 times. I really did. But I couldn't get past "Take A Way". Take... A... Way... Take a way. Take exactly one way. A way to take. I have three ways, you get to take one. Need a way? Take a way! Feel free to take a way from the way jar. Life finds a way... and then takes it.
- tasty_freeze 7y agoI don't understand your point. Caches (other the trivial ones) are organized into "ways". A given access will map into one of the ways of a set. The title is punning on "take a way" and "takeaway".
- loeg 7y agoIt's British for takeout, carry-out, or whatever you want to call restaurant food you pick up yourself.
- GordonS 7y agoNot quite - it's "take away", not "take a way" as used in the article.
- Josephineus 7y agoThe joke is that way prediction involves reading one way of a cache, not from the way jar, but from a set. Caches are divided into sets and ways in CPUs.
- Thorrez 7y agoDifferent thread, about the paper: https://news.ycombinator.com/item?id=22514099 https://news.ycombinator.com/item?id=22514099
- nieve 7y ago> The researchers also noted that unlike the Spectre and Meltdown vulnerabilities, the Take A Way exploits only leak a "few bits of metadata," as opposed to providing full access to data (example of Meltdown exploit here). Not good and leaked information about the manner in which a process is accessing memory is probably useful to some attacker out there, but thankfully it's not even in the same class as the actual memory content disclosure vulnerabilities..
- DevKoala 7y agoThe timing of this vulnerability release is hilarious. AMD had their financial analyst conference on Thursday afternoon. The stock rallied after market hours and ended positive on Friday while everything else tanked along with the US economy. That’s how good of a bet AMD is right now. These news are Intel sponsored. https://twitter.com/HardwareUnboxed/status/1236079970729865216 https://twitter.com/HardwareUnboxed/status/12360799707298652... Also the release does not quality as a new vulnerability vector like Spectre, just a new attack against a previously mitigated vulnerability. It honestly looks to me like anattempt to stop the AMD momentum. FD: The fastest processor I own is a 16 core Xeon, and is great. However, I have invested in AMD stock over the last year. I have a lot of respect for Intel engineering, but the AMD roadmap just looks stronger between now and 2022.
- GordonS 7y agoSomeone from the research group says they've been funded by Intel for 2 years, and have also published papers involving 10 Intel vulnerabilities during that time. https://twitter.com/lavados/status/1236088594584014848?s=19 https://twitter.com/lavados/status/1236088594584014848?s=19
- DevKoala 7y agoFair enough. The timing is still just perfect.
- vbezhenar 7y agoIt goes as I expected. As AMD gains more popularity and spotlight, more researchers will probe their chips and more bugs will be uncovered. The only reason Intel got so many vulnerabilities is their market position.
- willis936 7y agoDo you have anything concrete to back up such a soft claim?
- robdachshund 7y agoThe reason intel has so many vulnerabilities has a lot more to do with their CPUs still being heavily rooted in their ancient P6 architecture
- ibotty 7y agoquick link https://mlq.me/download/takeaway.pdf https://mlq.me/download/takeaway.pdf