2 ms·

I think you are referring to KTPI, but a) it might not be needed on recent CPUs that had meltdown-like issues patched, and b) in any case on CPUs that can tag p

I think you are referring to KTPI, but a) it might not be needed on recent CPUs that had meltdown-like issues patched, and b) in any case on CPUs that can tag pages with process identifiers (most of them these days), it can avoid TLB flushes most of the time. But I don't claim any specific knowledge of on these mitigations.

panzi 3y ago
Is the PID different when entering kernel space but still doing work for the calling PID?
- gpderetta 3y ago
  I don't think it is different, but it doesn't matter, the kernel can put whatever it wants in the register that is used to match the process identifier tag in the TLB.