On 24 January 2018 at 15:49, Michael Fothergill < michael.fotherg...@gmail.com> wrote:
> > > On 24 January 2018 at 14:15, Michael Fothergill < > michael.fotherg...@gmail.com> wrote: > >> >> >> On 24 January 2018 at 14:11, Vincent Lefevre <vinc...@vinc17.net> wrote: >> >>> On 2018-01-24 14:44:18 +0100, Sven Hartge wrote: >>> > Michael Fothergill <michael.fotherg...@gmail.com> wrote: >>> > > On 24 January 2018 at 12:58, Sven Hartge <s...@svenhartge.de> wrote: >>> > >>> > >> Michael Fothergill <michael.fotherg...@gmail.com> wrote: >>> > >>> > >> > The link within the above one: >>> > >>> https://gcc.gnu.org/ml/gcc/2018-01/msg00148.html >>> > >>> also has a link to the ftp download for the release candidate >>> version of >>> > >>> gcc 7.3 ie 7.3.0rc1 which does actually work for spectre and >>> retpoline. >>> > >>> > >> Debian Sid got gcc-7.3.0rc2 last night, the package is still named >>> gcc-7 >>> > >> (7.2.0-20) though. >>> > >>> > > Does that mean that if you upgrade to sid and installed gcc 7.2.0 you >>> > > would actually get 7.3.0rc2 in practice? >>> > >>> > Unless I interpret the changelog wrong: yes. >>> >> > > I have found a kernel image file here: > > https://packages.debian.org/experimental/linux-image-4.15.0-rc8-amd64 > > I think this will likely work OK with KPTI and retpoline. > > It's in debian experimental. > > If you can be sid and experimental together then I guess you can have gcc > 7.3 rc1 or 2 (or whatever it is) installed and then > install the image as a kernel upgrade not a kernel compilation: > > Something like this: > > # cat >> /etc/apt/preferences << EOF Package: * Pin: release > o=Debian,a=experimental Pin-Priority: 102 EOF # apt-cache policy # > shows/verifies the current preferences # echo "deb > http://deb.debian.org/debian experimental main" >> /etc/apt/sources.list # > apt-get update # apt-get -t experimental install linux-image-3.10-rc5-686-pae > > > > > Except here you would do: > > # apt-get -t experimental install linux-image-4.15.0-rc8-amd64 > > Then I would have thought KPTI and retpoline would be installed in a > relatively painless way if you don't mind running as sid. > > Cheers > > MF > Wait a minute. If the linux image kernel is a binary ie compiled then as long as it was compiled using a gcc compiler v 7.3 or greater then the retpoline and KPTI would correctly installed by default. So, if my understanding is correct then would that not mean you would not need to have v 7.3 of gcc installed locally so you would not need to become sid? Just a thought. MF > > > > > > > > > >> >>> But the changelogs don't mention anything about Spectre and retpoline. >>> >> >> It's OK. As long as you really do end up installing gcc 7.3.0 rc2 we >> know it can handle the compilation of kernel 4.14.14 correctly to >> make the KPTI and retpoline patches work........... >> >> So the changelog doesn't matter. >> >> Cheers >> >> MF >> >> >> >>> >>> -- >>> Vincent Lefèvre <vinc...@vinc17.net> - Web: <https://www.vinc17.net/> >>> 100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/> >>> Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon) >>> >>> >> >
