On Jan 13, 2018, at 22:20, Emmanuel Dreyfus <m...@netbsd.org> wrote: > > John Klos <j...@ziaspace.com> wrote: > >> FWIW, Intel updated their microcode on 8-Jan-2018: >> >> https://downloadcenter.intel.com/download/27431/ >> >> I can't find any documentation which shows what exactly is fixed for each >> family of processors. > > It does not seems to fix much. > > I tried the tests from git repository > http://github.com/IAIK/meltdown.git > > This is Linux-centric, but at least, the "secret" case seems to apply on > NetBSD. It reports vulnerability before (cpu0: microcode version 0x58, > platform ID 1) and after (cpu0: microcode version 0x80, platform ID 1) > microcode upgrade. > > And I do not have a spectre test case. Anyone has that?
My understanding is that the microcode update doesn't actually *fix* anything by itself. What it does is enable an OS to more easily fix things. The kernel would need to check for the new SPEC_CTRL CPUID bit, and if present, twiddle with the new speculation control-related MSRs at the appropriate times. -- Name: Dave Huang | Mammal, mammal / their names are called / INet: k...@azeotrope.org | they raise a paw / the bat, the cat / Telegram: @DahanC | dolphin and dog / koala bear and hog -- TMBG Dahan: Hani G Y+C 42 Y++ L+++ W- C++ T++ A+ E+ S++ V++ F- Q+++ P+ B+ PA+ PL++
