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Comment by thehardsphere | Hacker News Reader

We know that "AMD processors are not subject to the types of attacks that the kernel page table isolation feature protects against." E.g. that AMD does not need the patch that Intel does. That is not the same as saying AMD is not affected at all.

We do not know what the actual bug that prompted this activity is. Nobody has revealed that information. It is possible that the bug affects AMD also but does not require this patch.

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The followup sentence: "The AMD microarchitecture does not allow memory references, including speculative references, that access higher privileged data when running in a lesser privileged mode when that access would result in a page fault."

That is a pretty specific reference to the root of the problem, and a pretty clear indication that AMD's design decisions protect against whatever the attack is. Sure, we may find out that there is more to the attack than just speculative memory references, but so far what we have seen suggests a fairly specific vulnerability (that just happens to involve the particular design choices of a dominant chipmaker).

And, 17 hours later, we now know that there were three distinct vulnerabilities, of which one applies to AMD.

https://googleprojectzero.blogspot.com/2018/01/reading-privi...

Only under specific software configurations that are not enabled by default, or confined to a userspace single process (which is bad for web browsers running Javascript but not nearly as bad as the Intel-specific attacks). So while AMD is somewhat vulnerable, the most severe and easiest to exploit vulnerabilities are pretty specific to Intel. In a pedantic sense you were right, AMD chips are affected, but it is literally not on the same level as for Intel chips.

That's correct and it is a fair way to see it. However, Intel dragging two of its main competitors name into the limelight is a rather uncool move.

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