3 ms·
> or whether x86 hypervisors tend to provide RDRAND support. One issue that I've been wondering about is how safe this is. Presumably you can't let a VM use th
by als0 5y ago
> or whether x86 hypervisors tend to provide RDRAND support.
One issue that I've been wondering about is how safe this is. Presumably you can't let a VM use the RDRAND directly because it could starve the entropy of other VMs. Assuming that presumption is true, a hypervisor would need to manage that shared resource fairly amongst the VMs.
- asveikau 5y agoI don't know this for sure, but I'm not under the impression that RDRAND has the same "entropy as a scarce resource" or "block waiting on entropy" issue that the Linux apis have.
- dragontamer 5y agoRDSEED is actually what people want most of the time. RDRAND may return before sufficient entropy has been gathered. Basically, RDRAND was made first to be something like a hardware /dev/urandom. Of course, people started using RDRAND to generate RSA-keys or whatever, but the entropy may be depleted between uses. So you're supposed to use RDSEED whenever you need something that'd actually be truly random with a full set of entropy.
- als0 5y agoAh I realise I meant RDSEED