Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
raspberrypi.org
Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
1–10 of 232 posts
Re: Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
#2With all the news about these attacks lately, this is one of the best posts I've seen in explaining to less knowledgable people how exactly speculation causes a problem.
One question I still have that gets glossed over is how timing of instructions is captured.
Re: Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
#3This article wonderfully explains a complex context without losing a lot of relevant detail.
Re: Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
#4This is a good overview of modern, superscalar, out-of-order, speculative CPUs that literally any programmer could easily understand. Recommended reading for every single engineer in the whole world (who doesn't already understand this stuff from reading source material e.g., Google Zero post).
Re: Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
#5The best explanation of Meltdown I’ve read.
Re: Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
#6[deleted]
Re: Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
#7This is a good overview of modern, superscalar, out-of-order, speculative CPUs that literally any programmer could easily understand. Recommended reading for every single engineer in the whole world (who doesn't already understand this stuff from reading source material e.g., Google Zero post).
Agreed. This was the best of the explanations I've read, and it helped me to finally wrap my mind around the exploits.
Re: Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
#8With all the news about these attacks lately, this is one of the best posts I've seen in explaining to less knowledgable people how exactly speculation causes a problem. One question I still have that gets glossed over is how timing of instructions is captured.
One way would be to use the rdtsc instruction, which reports how many cycles have been executed since the processor was reset.
Re: Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
#9With all the news about these attacks lately, this is one of the best posts I've seen in explaining to less knowledgable people how exactly speculation causes a problem. One question I still have that gets glossed over is how timing of instructions is captured.
One way would be to use the rdtsc instruction, which reports how many cycles have been executed since the processor was reset.
Which is precisely why Firefox is releasing an update that tweaks high resolution timing. I guess tweaks probably means breaks for some uses cases but that’s likely unavoidable and worth it.
Re: Why Raspberry Pi Isn't Vulnerable to Spectre or Meltdown
#10With all the news about these attacks lately, this is one of the best posts I've seen in explaining to less knowledgable people how exactly speculation causes a problem. One question I still have that gets glossed over is how timing of instructions is captured.
One way would be to use the rdtsc instruction, which reports how many cycles have been executed since the processor was reset.
Using rdtscp is better in this case than rdtsc, because it's a serializing instruction. So speculation (instruction reordering) itself doesn't affect the results.