> > In the past the only guidance was to not load microcode at the same time to > the > > thread siblings of a core. We now have new guidance that the sibling must be > > spinning and not doing other things that can introduce instability around > loading > > microcode. > > Document that properly in the Intel SDM, *please*.
yes we will update the SDM, just that is a much longer process than sending code out. > > While at it, please verify with the microcode teams that the requirement > for 16-byte alignment of the microcode update as present in the Intel > SDM still stands. I'd be surprised if it did not. >Linux does not enforce it on the early microcode > update loader when using an initramfs (but userspace can work around > that, and iucode_tool --early-fw does so). If that 16-byte alignment is > important, I could dust off some patches that fix it. hmm wonder what those tools do nowadays; Intel publishes the microcode in the linux native format since some time (and the .dat format is about to go away entirely)