> Now you've turned specific access patterns into "attack attempts",
We already have error correction detection available to us and it's in use today.
> RAM should always hold what was last written to it, under all conditions of software accesses.
OK? That's what anyone who is advocating for ECC is already advocating for. ECC is error correcting up to 1 bit and error detecting up to 2 bits. The goal is to ensure that the property you've described holds.
> It only got created because the RAM companies have forsaken correctness,
This problem exists because... physics. Do you actually have a design for RAM that can match today's cell density while somehow providing perfect isolation? Saying this problem didn't exist 15 years ago is like saying that malware didn't impact the abacus - RAM 15 years ago was designed completely differently, and had considerably lower capabilities in terms of storage and latency.
And for reference, hamming codes (which back ECC) were created in the 1950s for error correction in punch cards. This is not a new problem.
ECC is the existing, obvious solution to this problem, it just wasn't built for this threat - but it's an excellent, proven method for correcting bit flips. Even without being designed to prevent rowhammer it already makes the attack much slower, less likely to succeed, and easier to detect (just monitor for a massive spike in ecc corrections).
Trying to design high density RAM that maintains perfect isolation seems pointless. Improving ECC or ECC-like approaches is likely going to be much more effective.
We already have error correction detection available to us and it's in use today.
> RAM should always hold what was last written to it, under all conditions of software accesses.
OK? That's what anyone who is advocating for ECC is already advocating for. ECC is error correcting up to 1 bit and error detecting up to 2 bits. The goal is to ensure that the property you've described holds.
> It only got created because the RAM companies have forsaken correctness,
This problem exists because... physics. Do you actually have a design for RAM that can match today's cell density while somehow providing perfect isolation? Saying this problem didn't exist 15 years ago is like saying that malware didn't impact the abacus - RAM 15 years ago was designed completely differently, and had considerably lower capabilities in terms of storage and latency.
And for reference, hamming codes (which back ECC) were created in the 1950s for error correction in punch cards. This is not a new problem.
ECC is the existing, obvious solution to this problem, it just wasn't built for this threat - but it's an excellent, proven method for correcting bit flips. Even without being designed to prevent rowhammer it already makes the attack much slower, less likely to succeed, and easier to detect (just monitor for a massive spike in ecc corrections).
Trying to design high density RAM that maintains perfect isolation seems pointless. Improving ECC or ECC-like approaches is likely going to be much more effective.