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At some point, I bet someone in a design meeting said "Hey, I think this might compromise security, can we study that before implementing it?" And the decision

At some point, I bet someone in a design meeting said "Hey, I think this might compromise security, can we study that before implementing it?" And the decision to implement it without that study, or despite it, was made. Because implementing it increased performance which made the numbers which captured market share. It's not like the processor designed itself that way. Humans made choices along the way, and every choice is a tradeoff. Execution-time attacks and other sidechannel leakage have been well-known for years, and I can't imagine that at a place like Intel, nobody had heard of that.

gary__ 7y ago
"At some point, I bet someone in a design meeting said "Hey, I think this might compromise security, can we study that before implementing it?" And the decision to implement it without that study, or despite it, was made." Because we should assume all your past missteps were due to willful negligence? Yeah, let's not just start making shit up to support the group think outrage.
- dgoldstein0 7y ago
  agree, I really doubt people were like "let's compromise security for performance". More likely it was something like: "hey here's an idea for how we can get more performance" "convince me it's correct" "oh, that's cause X, Y, Z..." and either no one thought about the security implications, or no one could come up with a security problem at design time - likely just no one thought about side channel problems.
dfrage 7y ago
> Because implementing it increased performance which made the numbers which captured market share. More than the following big things, in both directions? - A consistent fabrication advantage until very recently? That's said to have wiped out a generation of clever hardware architects, when Intel beat their best efforts with their next process node. - Falling behind AMD with the Netburst "marchitecture", the front side bus memory bottleneck, and only supporting Itanium as a 64 bit architecture? - Reversing the above by licencing AMD64, reverting to the same Pentium Pro style design AMD was using, and copying their ccNUMA multi-chip layout (each is directly attached to memory, with fast connections between them). - AMD losing the plot after the K8 microarchitecture, including putting a huge amount of capital into buying ATI instead of pushing their CPU advantage? And then having to sell off their fabs, putting them at a permanent disadvantage until Intel's "10nm" failed? (And what happened to the K9??) - Anticompetitive marketing and sales? > Execution-time attacks and other sidechannel leakage have been well-known for years, and I can't imagine that at a place like Intel, nobody had heard of that. The strange thing is that security researchers assumed for years that Intel was accounting for this, when it turned out not a single one of AMD, ARM, IBM POWER and mainframe/Z, Intel, MIPS, or SPARC did?
PeterisP 7y ago
Why do you think that it's likely that someone in Intel design meetings had thought of that if literally noone outside Intel did for many years? It obviously wasn't obvious to the very, very many people worldwide who know about execution-time attacks and other sidechannel leakage, as it took more than 10 years of almost every chip worldwide being vulnerable until it was noticed. It's not as if some 2016 design tradeoff suddenly enabled Meltdown. Engineers were carefully studying competitor's chip designs, and none of them noticed that flaw for more than a decade.
- viraptor 7y ago
  Even better: at least one person documented thinking about this issue, trying to exploit it and failing - showing that even if you could come up with this, it was really non trivial to achieve.
- throwaway2048 7y ago
  This is a really weak argument because plenty of hilariously stupid and easy to exploit bugs are found in extremely widely used software all the time.

gary__ 7y ago

"At some point, I bet someone in a design meeting said "Hey, I think this might compromise security, can we study that before implementing it?" And the decision to implement it without that study, or despite it, was made." Because we should assume all your past missteps were due to willful negligence? Yeah, let's not just start making shit up to support the group think outrage.

dgoldstein0 7y ago
agree, I really doubt people were like "let's compromise security for performance". More likely it was something like: "hey here's an idea for how we can get more performance" "convince me it's correct" "oh, that's cause X, Y, Z..." and either no one thought about the security implications, or no one could come up with a security problem at design time - likely just no one thought about side channel problems.

dfrage 7y ago

> Because implementing it increased performance which made the numbers which captured market share. More than the following big things, in both directions? - A consistent fabrication advantage until very recently? That's said to have wiped out a generation of clever hardware architects, when Intel beat their best efforts with their next process node. - Falling behind AMD with the Netburst "marchitecture", the front side bus memory bottleneck, and only supporting Itanium as a 64 bit architecture? - Reversing the above by licencing AMD64, reverting to the same Pentium Pro style design AMD was using, and copying their ccNUMA multi-chip layout (each is directly attached to memory, with fast connections between them). - AMD losing the plot after the K8 microarchitecture, including putting a huge amount of capital into buying ATI instead of pushing their CPU advantage? And then having to sell off their fabs, putting them at a permanent disadvantage until Intel's "10nm" failed? (And what happened to the K9??) - Anticompetitive marketing and sales? > Execution-time attacks and other sidechannel leakage have been well-known for years, and I can't imagine that at a place like Intel, nobody had heard of that. The strange thing is that security researchers assumed for years that Intel was accounting for this, when it turned out not a single one of AMD, ARM, IBM POWER and mainframe/Z, Intel, MIPS, or SPARC did?

PeterisP 7y ago

Why do you think that it's likely that someone in Intel design meetings had thought of that if literally noone outside Intel did for many years? It obviously wasn't obvious to the very, very many people worldwide who know about execution-time attacks and other sidechannel leakage, as it took more than 10 years of almost every chip worldwide being vulnerable until it was noticed. It's not as if some 2016 design tradeoff suddenly enabled Meltdown. Engineers were carefully studying competitor's chip designs, and none of them noticed that flaw for more than a decade.

viraptor 7y ago
Even better: at least one person documented thinking about this issue, trying to exploit it and failing - showing that even if you could come up with this, it was really non trivial to achieve.
throwaway2048 7y ago
This is a really weak argument because plenty of hilariously stupid and easy to exploit bugs are found in extremely widely used software all the time.