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From: Stefan Monnier <monnier@iro.umontreal.ca>
Newsgroups: comp.arch
Subject: Re: Privilege Levels Below User
Date: Thu, 13 Jun 2024 10:56:16 -0400
Organization: A noiseless patient Spider
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> Rowhammer can modify nearby lines, not just the ones that are being
> hammered, right? How do you guarantee that all neighbors will also
> be refreshed?

I don't know the answer to this one.

> Similarly, if the accesses are LOCK XADD operations, and you have multiple
> CPUs (or cores not sharing a common last level cache, then I don't see any
> way to avoid those accesses from making it all the way to the RAM chips?

But I can answer that one: don't!
I.e. the DRAM is attached to one and only one CPU.  Any other CPU that
wants to access that DRAM has to do it through that DRAM's CPU, which
will make it pass through its shared "last level" cache.


        Stefan