I would tend to agree, unfortunately there are too many issues in too many different parts meaning you can't just easily enumerate them until you've specifically looked into them for an extended period of time.
Linus is just ranting and trying to be smart. All hardware and software evolve over many years and that is fairly normal. You don't make the perfect hardware or software on just first release. Linux wouldn't be what it is today without billions of dollars and hundreds of engineers spent by big tech companies.
I think he may be refiring to some obvious mistakes like: - How you port applications written in x86 and arm to risc-v - Security (how the cache memory is managed) - Having support for compilers of different programming languages - Having a 64 bit integer to represent time - Having take care of thermals when the chips is at its top performance - Get a deal with hardware and software companies (specially OS) to use your chips - Also how do you deprecate instructions you no longer use (like intel with x86)
The problem is that new people aren't taught the history of the fields (hard and soft). They come in with the confident arrogance of youth and faith in their ideas, oblivious to the past failures, which they faithfully reproduce.
@@blvckbytes7329 well, when the old farts do not publish their failures, how could we? I can vividly remember all those time my wife came back from a conference where she learned on a side note in a poster session that the method they were trying to develop had already been tested and failed years ago with ZERO publications on that. That makes teaching how things DON'T work much harder (and sometimes, they didn't work in the past, but ended up working later on when the _actual_ problem was identified)
David Petersen was involved in it and he has been around since 1990 and literally co-wrote the book on procesor design with Hennessey and won a Turing Award. If you read the original papers they have rationale why they didn’t chose and existing architecture. So how much more experience and pedigree would you like?
I disagree mostly with this. Most of the issues that come up aren’t really classifiable as ‘mistakes’ - they’re just shortcomings that were very hard to imagine or predict ahead of time. Fundamental mistakes are very well avoided since their effects are mostly rather obvious, and they are mostly well listed as shortcomings of previous iterations. It’s the insidious ones that only rear their head once someone manages to find a way to make it go wrong that bite us. I think those are what Linus is referring to… the hardware choices that end up making it impossible to implement reasonable code safety without compromising performance or flexibility of systems. Any new ISA is bound to present new opportunities for people to break it in this way.
I think t would be awesome if Linus Torvalds joined some steering/advisory group of RISC-V and help them avoid as many mistakes as possible. But still better having open and royalty-free ISA then closed one, even if they would have the same mistakes.
It kinda sneaks up on you. I was 20 at the morning mirror and went about doing things and I just noticed the other day that I'm 70... Just walk around a lot, eat only what you need, and work on interesting things. It's not so bad. Oh, and never look back, only forward...
I'm tired of reading people blame Linus for not providing examples. It's just what you were expecting because of the title of this video. In fact, there wasn't even a question about risc-v mistakes from the interviewer, Linus just quickly mentioned it.
Not sure, but, it is not open source architecture, only ISA specification is open source, implementation is on per implementer. Makes a big difference.
Correct, and I think the main advantage will be in compatibility between different RISC-V implementations. Ultimately the benefits will be in the software ecosystem, not in whose CPU is a tad faster.
I think he is referring mainly to those security aspects that, through speculative execution, generate the well-known Spectre and Meltdown attacks. These allow the memory protection offered by the MMU to be breached. It is clear that implementing a hardware solution or mitigation would have an impact on performance, but doing it in software as it is currently implemented is even greater. Also beleve that nobody should doubt LT's authority when it comes to giving his opinion on these issues, being a person who, beyond his public notoriety, has been programming at a low level for more than 50 years. (He has already said that he often writes code in C and then observes how it is translated into Assembler by the compiler; and rewrites it if necessary, so that the result is the most efficient. I doubt that those who criticize have ever tried something like that...) Regards
RISC-V is literally just an ISA, What Linus is probably referring hardware that will be feature the RISC-V ISA, because these "mistakes" and "issues" occur at a level lower than ISA itself, i.e. at Micro Architecture Level.
J'ai vu hier une vidéo qui affirmait que la fondation Linux ne consacre plus que 2% de son CA au développement du noyau. Tout le reste, c'est des projets de multinationales membres du CA qui utilisent sûrement le noyau mais n'ont plus rien à voir avec les logiciels libres. Alors je voudrais pas casser l'ambiance, mais avant de parler des erreurs des autres architectures, je vois en ce moment des erreurs de noyaux régressives. Sur la Mint l'autre jour c'était la perte du port HDMI lors d'une montée du noyau officiel sur un portable ASUS. Sur une machine fixe montée, passée de la Ubuntu 20.04 à 22.04, c'est la mise en veille mémoire qui plante désormais sur un contrôleur SATA additionnel avec un noyau 5.15, avec une erreur sata_pmp_eh_recover.isra, là où le noyau 5.4 n'avait pas de soucis. Bref, même si le noyau est robuste, et qu'on peut heureusement revenir à d'anciennes versions, un usager normal et basique se posera quand même des questions. Pour ma part, la principale erreur des distributions, c'est de forcer la mise à jour des noyaux, quand la machine marche parfaitement bien, et de ne pas offrir un mécanisme graphique de retour à l'ancien noyau quand les choses se passent mal... Enfin, et là c'est plus un reproche global ici sur l'interview : je veux bien que M. Torvalds soit un excellent ingénieur. Mais sans les logiciels libres et la licence GPL de Richard Stallman, il n'est pas sûr que son noyau aurait eu le succès qu'il a. Or je ne vois jamais de reportages sur R.M.S., luttant aujourd'hui contre un cancer, qui certes a une autre vision, mais qui au fond reste le véritable papa des logiciels libres, et à qui on doit d'avoir aujourd'hui une vraie alternative aux OS privateurs de liberté. Une fois encore, on cache les origines de GNU/Linux, en glorifiant un ingénieur qui est tout sauf un libriste, et en oubliant que le monde du Libre, c'est aussi une philosophie, une vision du monde, la défense de la démocratie et de la souveraineté numérique.
For those wanting Torvalds to simply give a list of the mistakes, you have to realize that in order to be able to list those mistakes, one has to spend CONSIDERABLE time diving deep into the RiscV architecture, while having a LOT of experience optimizing systems for other architectures and seeing them improve over the years. Torvalds is probably not the right person for that, and his answer shows me that he knows that. He is just warning the RiscV team that, watch out, the path you are treading is not new, others have been there before, and you should learn from them. Probably the best people to talk with are compiler builders, people who implement e.g. the Java virtual machine on specific platforms, people who design and study performance benchmarks, and those who optimize system performance for various computing platforms.
Isa design and processor manufacturing are rellatively independent. This even was a motivator for amd to separate it's foundries as another company years ago The techniques and tecnologies for wafer production that actually translate a chip design into reality are mostly trade secret kept at closed doors.
My home server is running on RISC-V hardware and yes, there are gaps but mostly with embedded chipsets having no drivers like e.g. iGPUs and "closed source" drivers not beeing rebased to current kernels. But the platform itself is rock solid. I can not complain.
He is just giving his opinion based on his experience of decades. Maybe his opinion is more credible than a fan boy with zero experience who only base his opinions on ear say and trends.
@@estranhokonsta decades of experience of what exactly? how is his experience related to ISA design? his guess is entirely uneducated and completely unexplained. also funny when you say stuff about fanboys when that's what you are literally being in your comment
@@HolarMusic Lol. Me a fan of him? I do not even use linux or wish to use it. The rare occasions i used it were because i needed to and certainly not because i wanted to. But besides that, it doesn't mean that i am blind to who is the expert here in this question. Him or you? Who do you think i bet my money on?
Torvolds complaining about this but not pushing for professionals in these spaces to share and exchange knowledge to bridge these gaps. It's a hard gap to bridge but if there were spaces where these ideas and documents can be aggregated to establish mutual understanding
In my honorable opinion, recent architectures as x86, arm and risc-v are the same bloatware on silicon. I don't need read books of many thousands of pages of these chips (that deviate the attention). I need simple architectures, safe architectures, minimalist requirements, books of fewer hundreds of pages, etc.
The base RISC-V integer ISA spec may be a few hundred pages but by the time you add in the specs for the many extensions required in many use cases you're going to be heading towards a lot more than that...
That sounds great until you have enough silicon for vector units, and you need add a new SIMD ISA to take advantage of it. Most of the crufty old instructions just take up a minuscule amount of space in microcode ROM, and they don't "bloat" the CPU.
The whole point is to make money not a very efficient chip, just in 1 month someone will says its obsolete off of a breath of air. x-86 lives on the desktop and server. Arm for phone and tablets.
![BOWKYLION - เจ้านายคะ (work-life imbalance) [Official MV]](http://i.ytimg.com/vi/6bFj8G2pOi4/mqdefault.jpg)
he should expose the mistakes rather than saying "same mistakes"
I would tend to agree, unfortunately there are too many issues in too many different parts meaning you can't just easily enumerate them until you've specifically looked into them for an extended period of time.
Linus is just talking sh*t like usual.
Ditto. He wording nearly implied ARM resolved the mistakes. Need more elaboration instead of unhelpful assertions.
Linus has no clue about most things.. same as usual
Linus is just ranting and trying to be smart. All hardware and software evolve over many years and that is fairly normal. You don't make the perfect hardware or software on just first release. Linux wouldn't be what it is today without billions of dollars and hundreds of engineers spent by big tech companies.
What are the mistakes?
they will not tell you because those from arm will let you figure out and save their lives.
I think he may be refiring to some obvious mistakes like:
- How you port applications written in x86 and arm to risc-v
- Security (how the cache memory is managed)
- Having support for compilers of different programming languages
- Having a 64 bit integer to represent time
- Having take care of thermals when the chips is at its top performance
- Get a deal with hardware and software companies (specially OS) to use your chips
- Also how do you deprecate instructions you no longer use (like intel with x86)
Try making sense of the plethora, and rapidly increasing number, of RISC-V extensions and development tool support for same, for example... 🤯😖
check out the other video: Linux Torvalds: Speaks on Linux Hardware SECURITY Issues
I also have the same question and reading the comments still doesn't make me understand. I really curious what were wrong and what they should be.
The problem is that new people aren't taught the history of the fields (hard and soft). They come in with the confident arrogance of youth and faith in their ideas, oblivious to the past failures, which they faithfully reproduce.
This! In so many scientific fields... We're failing miserably on educating young minds.
@@blvckbytes7329 well, when the old farts do not publish their failures, how could we? I can vividly remember all those time my wife came back from a conference where she learned on a side note in a poster session that the method they were trying to develop had already been tested and failed years ago with ZERO publications on that. That makes teaching how things DON'T work much harder (and sometimes, they didn't work in the past, but ended up working later on when the _actual_ problem was identified)
David Petersen was involved in it and he has been around since 1990 and literally co-wrote the book on procesor design with Hennessey and won a Turing Award. If you read the original papers they have rationale why they didn’t chose and existing architecture. So how much more experience and pedigree would you like?
I disagree mostly with this. Most of the issues that come up aren’t really classifiable as ‘mistakes’ - they’re just shortcomings that were very hard to imagine or predict ahead of time. Fundamental mistakes are very well avoided since their effects are mostly rather obvious, and they are mostly well listed as shortcomings of previous iterations. It’s the insidious ones that only rear their head once someone manages to find a way to make it go wrong that bite us. I think those are what Linus is referring to… the hardware choices that end up making it impossible to implement reasonable code safety without compromising performance or flexibility of systems.
Any new ISA is bound to present new opportunities for people to break it in this way.
It's the bussines. They dont care about advancement, only money. Evolution disolve status quo.
I think t would be awesome if Linus Torvalds joined some steering/advisory group of RISC-V and help them avoid as many mistakes as possible. But still better having open and royalty-free ISA then closed one, even if they would have the same mistakes.
I love the part when he lists the mistakes.
Maybe the RISC-V-guys should have a talk with Linus Torvalds?
Remember Transmeta?
@@StringerNews1 Vaguely. What's up with them?
@@ikemkrueger nothing any more. But it was a CPU company that Linus worked for. He'd be able to help with RISC-V.
I don't remember Linus being this old
yet you've both gotten older the same amount
It kinda sneaks up on you. I was 20 at the morning mirror and went about doing things and I just noticed the other day that I'm 70... Just walk around a lot, eat only what you need, and work on interesting things. It's not so bad. Oh, and never look back, only forward...
It's the recent update.
I'm tired of reading people blame Linus for not providing examples. It's just what you were expecting because of the title of this video. In fact, there wasn't even a question about risc-v mistakes from the interviewer, Linus just quickly mentioned it.
Not sure, but, it is not open source architecture, only ISA specification is open source, implementation is on per implementer. Makes a big difference.
Correct, and I think the main advantage will be in compatibility between different RISC-V implementations. Ultimately the benefits will be in the software ecosystem, not in whose CPU is a tad faster.
One word. Transmeta. 😂
I think he is referring mainly to those security aspects that, through speculative execution, generate the well-known Spectre and Meltdown attacks. These allow the memory protection offered by the MMU to be breached. It is clear that implementing a hardware solution or mitigation would have an impact on performance, but doing it in software as it is currently implemented is even greater.
Also beleve that nobody should doubt LT's authority when it comes to giving his opinion on these issues, being a person who, beyond his public notoriety, has been programming at a low level for more than 50 years. (He has already said that he often writes code in C and then observes how it is translated into Assembler by the compiler; and rewrites it if necessary, so that the result is the most efficient. I doubt that those who criticize have ever tried something like that...) Regards
So like Linus repeated all Unix mistakes again with Linux
Regular stuff. The thing is - how first a platform learns from the mistake.
where's unix?, a yes, dead
Yes, they did. Big companies have poured billions in bringing UNIX goodies to Linux.
@@subway394 lmao what
Unix is some Kernel with a certain userland, aside from the trademark. He's doing the Kernel, GNU and others the userland.
No examples?
Cool video and interview of Linus Torvalds!
RISC-V is literally just an ISA, What Linus is probably referring hardware that will be feature the RISC-V ISA, because these "mistakes" and "issues" occur at a level lower than ISA itself, i.e. at Micro Architecture Level.
J'ai vu hier une vidéo qui affirmait que la fondation Linux ne consacre plus que 2% de son CA au développement du noyau. Tout le reste, c'est des projets de multinationales membres du CA qui utilisent sûrement le noyau mais n'ont plus rien à voir avec les logiciels libres. Alors je voudrais pas casser l'ambiance, mais avant de parler des erreurs des autres architectures, je vois en ce moment des erreurs de noyaux régressives. Sur la Mint l'autre jour c'était la perte du port HDMI lors d'une montée du noyau officiel sur un portable ASUS. Sur une machine fixe montée, passée de la Ubuntu 20.04 à 22.04, c'est la mise en veille mémoire qui plante désormais sur un contrôleur SATA additionnel avec un noyau 5.15, avec une erreur sata_pmp_eh_recover.isra, là où le noyau 5.4 n'avait pas de soucis. Bref, même si le noyau est robuste, et qu'on peut heureusement revenir à d'anciennes versions, un usager normal et basique se posera quand même des questions. Pour ma part, la principale erreur des distributions, c'est de forcer la mise à jour des noyaux, quand la machine marche parfaitement bien, et de ne pas offrir un mécanisme graphique de retour à l'ancien noyau quand les choses se passent mal... Enfin, et là c'est plus un reproche global ici sur l'interview : je veux bien que M. Torvalds soit un excellent ingénieur. Mais sans les logiciels libres et la licence GPL de Richard Stallman, il n'est pas sûr que son noyau aurait eu le succès qu'il a. Or je ne vois jamais de reportages sur R.M.S., luttant aujourd'hui contre un cancer, qui certes a une autre vision, mais qui au fond reste le véritable papa des logiciels libres, et à qui on doit d'avoir aujourd'hui une vraie alternative aux OS privateurs de liberté. Une fois encore, on cache les origines de GNU/Linux, en glorifiant un ingénieur qui est tout sauf un libriste, et en oubliant que le monde du Libre, c'est aussi une philosophie, une vision du monde, la défense de la démocratie et de la souveraineté numérique.
No specifics, just vibes and aphorisms
RISC-V is an ISA. The microarch (where the sec bugs happen) is free to be anything.
Is the complete interview available?
still don't get an up-to-date and *working* webbrowser on the pi4 🧐
Selling point of RiscV, is free 😂
How do we avoid repeating mistakes made in past?
usually learning and talking with the people that already saw these mistakes, like linus in this case
Generally, I think we need to create a standard how-to which will be the "go-to" when making some things
For those wanting Torvalds to simply give a list of the mistakes, you have to realize that in order to be able to list those mistakes, one has to spend CONSIDERABLE time diving deep into the RiscV architecture, while having a LOT of experience optimizing systems for other architectures and seeing them improve over the years. Torvalds is probably not the right person for that, and his answer shows me that he knows that. He is just warning the RiscV team that, watch out, the path you are treading is not new, others have been there before, and you should learn from them.
Probably the best people to talk with are compiler builders, people who implement e.g. the Java virtual machine on specific platforms, people who design and study performance benchmarks, and those who optimize system performance for various computing platforms.
The advantage of Riscv mistakes is that they will be publicly known, so they can ne taught for future generations.
RISC-V has China government funding or infinite funding
Future is unpredictable from some reason
So what?
Relevant here is that the manufacturing processes have improved. Its not like risc v will have to wait 20 years before 7nm process
Isa design and processor manufacturing are rellatively independent. This even was a motivator for amd to separate it's foundries as another company years ago
The techniques and tecnologies for wafer production that actually translate a chip design into reality are mostly trade secret kept at closed doors.
They will be fixed with riscVI
RiscVIM
Bring back PowerPC
man, he really aged.
He's just speculating that they *will* make the same mistakes and bases it on nothing
This is just blatant clickbait
My home server is running on RISC-V hardware and yes, there are gaps but mostly with embedded chipsets having no drivers like e.g. iGPUs and "closed source" drivers not beeing rebased to current kernels. But the platform itself is rock solid. I can not complain.
It's normal to make mistakes, but RISC-V will hopefully make less mistakes.
He is just giving his opinion based on his experience of decades. Maybe his opinion is more credible than a fan boy with zero experience who only base his opinions on ear say and trends.
@@estranhokonsta decades of experience of what exactly? how is his experience related to ISA design? his guess is entirely uneducated and completely unexplained.
also funny when you say stuff about fanboys when that's what you are literally being in your comment
@@HolarMusic Lol. Me a fan of him? I do not even use linux or wish to use it. The rare occasions i used it were because i needed to and certainly not because i wanted to.
But besides that, it doesn't mean that i am blind to who is the expert here in this question.
Him or you?
Who do you think i bet my money on?
computers are bad idea, any attempts to make new computers is repeating the same mistake
Torvolds complaining about this but not pushing for professionals in these spaces to share and exchange knowledge to bridge these gaps. It's a hard gap to bridge but if there were spaces where these ideas and documents can be aggregated to establish mutual understanding
Spoken by a guy who doesn't know how to design a driver interface.
In my honorable opinion, recent architectures as x86, arm and risc-v are the same bloatware on silicon. I don't need read books of many thousands of pages of these chips (that deviate the attention). I need simple architectures, safe architectures, minimalist requirements, books of fewer hundreds of pages, etc.
The base RISC-V integer ISA spec may be a few hundred pages but by the time you add in the specs for the many extensions required in many use cases you're going to be heading towards a lot more than that...
That sounds great until you have enough silicon for vector units, and you need add a new SIMD ISA to take advantage of it. Most of the crufty old instructions just take up a minuscule amount of space in microcode ROM, and they don't "bloat" the CPU.
Otherwise you are saying EE is too complicated.
I'm glad we have such thorough documentation
😂 I think you mean humble, not honorable, or do you really mean honorable?
on serious side: is there any simple, secure, and minumalist ISA? if not,vwhy no one make it?
The whole point is to make money not a very efficient chip, just in 1 month someone will says its obsolete off of a breath of air. x-86 lives on the desktop and server. Arm for phone and tablets.
More efficient chips do often make more money though