Re:The mysterious case of the Linux Page Table Isolation pat...
by thrill on Monday January 01, 2018 @12:12PM
(#16046863)
The bit flip would be done in a normal fashion - i.e. a command issued that changed the memory location, and hence updates the checksum. The occasional (about one bit flip per Terabyte per hour I think, on average) stray cosmic ray inducing a momentary over-voltage causing the checksum to now disagree would hopefully be within the design's ability to flip back.
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Re:The mysterious case of the Linux Page Table Isolation pat...
by rocqua on Monday January 01, 2018 @02:48PM
(#16047668)
That's not how rowhammer works.
It's a hardware level thing. Essentially, when you start rapidly flipping a single bit, that starts to 'leak' some current to the adjacent physical bits. This then allows you to flip a single bit. Especially if you can control bits on both sides of your target.
It's like you are using the bits you can control to 'simulate' an actual stray cosmic ray.