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0 pointsdpwm6y ago0 comments

> Spectre/Meltdown, which leak the speculative information via the cache side-channel, completely blindsided the architecture community; it wasn't just one incompetent company.

In the x86 space, Meltdown absolutely was down to one company apparently deciding to over-optimize for performance.

I can't find it now, but I remember reading a thread from (I think) the OpenBSD devs about how the Intel MMU documentation described fairly sane behaviours and how far the reality deviated from the documentation.

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dfrage6y ago

> In the x86 space, Meltdown absolutely was down to one company

Serious weasel wording, outside of x86 space every other high end architecture also had Meltdown issues, ARM, and IBM's POWER and mainframe designs.

roblabla6y ago

Erm, no? Meltdown was intel only. Spectre affects absolutely every architecture with speculative execution, but Meltdown (which allows crossing process and security boundaries) are absolutely unique to Intel.

dfrage6y ago

Erm, check out Wikipedia https://en.wikipedia.org/wiki/Meltdown_(security_vulnerabili... and follow the links? Meltdown is CVE-2017-5754, see: https://developer.arm.com/support/arm-security-updates/specu... where as I recall ARM initially described the Cortex-A75 as having a "variant", but now just lumps it in with the CVE. And the IBM info is also there, POWER7+ through POWER9, and per Red Hat, mainframe/System Z.

floatboth6y ago

Everyone who does speculative execution had Spectre issues, but Meltdown-style vulnerabilities have been mostly Intel-exclusive. These new ones are too.

dfrage6y ago

Maybe because Intel has shipped a thousand more SKUs and millions more CPUs with Meltdown than ARM, for which the Cortex-A75 was a new design, and IBM, which doesn't ship huge numbers of either POWER or mainframe CPUs??

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0 pointsdpwm6y ago0 comments

> Spectre/Meltdown, which leak the speculative information via the cache side-channel, completely blindsided the architecture community; it wasn't just one incompetent company.

In the x86 space, Meltdown absolutely was down to one company apparently deciding to over-optimize for performance.

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dfrage6y ago

> In the x86 space, Meltdown absolutely was down to one company

Serious weasel wording, outside of x86 space every other high end architecture also had Meltdown issues, ARM, and IBM's POWER and mainframe designs.

roblabla6y ago

dfrage6y ago

floatboth6y ago

Everyone who does speculative execution had Spectre issues, but Meltdown-style vulnerabilities have been mostly Intel-exclusive. These new ones are too.

dfrage6y ago

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