As far as I understood, the solution to this in sandboxes such as the js world, is simply to deny anyone using timers with a resolution that could reveal cache misses. How much is software really relying on timers with this resolution? What would it mean if CPU manufacturers simply gave up and said "to mitigate side channels, you can't have a clock that is so accurate that it lets you measure whether X has happened because knowing that is equivalent to reading any memory".
Or, instead of detecting various things and flushing out sensitive data on some context switch, the CPU just adds noise to the timers instead? I'm gussing this is a complete no-go, but I'm wondering why it is?
Or, instead of detecting various things and flushing out sensitive data on some context switch, the CPU just adds noise to the timers instead? I'm gussing this is a complete no-go, but I'm wondering why it is?