[coreboot] Rowhammer protection via increased ecc scrub rate?

[Timothy Pearson]

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On 02/12/2017 05:49 PM, Taiidan at gmx.com wrote:
> I am wondering if increasing the ECC scrub rate with nvramcui will
> improve rowhammer protection on the various coreboot fam15h boards, and
> if there is any downside to putting it at the fastest setting.
> Default is 640ns but it can go down to 40ns.

In general, no.  You either have rowhammer protection in terms of DIMMs
that are very unlikely to flip, in which case standard ECC will help, or
you have DIMMs that will generally flip even before ECC scrub can "fix"
the errors.

With ECC in general, the most likely result of a successful
rowhammer-based bit flip is a double fault found during scrub, with a
subsequent machine reset.

- -- 
Timothy Pearson
Raptor Engineering
+1 (415) 727-8645 (direct line)
+1 (512) 690-0200 (switchboard)
https://www.raptorengineering.com
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