* Borislav Petkov <b...@alien8.de> wrote: > On Wed, Nov 30, 2016 at 12:34:55PM -0800, Andy Lutomirski wrote: > > Aside from being excessively slow, CPUID is problematic: Linux runs > > on a handful of CPUs that don't have CPUID. MOV to CR2 is always > > available, so use it instead. > > > > Signed-off-by: Andy Lutomirski <l...@kernel.org> > > --- > > arch/x86/include/asm/processor.h | 31 ++++++++----------------------- > > 1 file changed, 8 insertions(+), 23 deletions(-) > > Looks nice. > > I'm wondering if we should leave this one in tip for an additional cycle > to have it tested on more hw. I know, it is architectural and so on but > who knows what every implementation actually does...
I think -tip and "upstream of the day" mostly gets tested on relatively recent x86 hardware - proven by the fact that these regressions are many months old. The reason v4.9 got extra testing is the announced Long Term Support (LTS) aspect: more, older, weirder hardware is being tested because it's going to be a very popular base kernel. So the best option would be to get these fixes into -tip, make sure it's sane all around and works on hardware that gets tested on bleeding edge kernels, then push it upstream sooner rather than later and also have Cc:stable tags on the obvious fixes, and handle any eventual fallout as it happens. That's the best we can do I think. Thanks, Ingo