Re: [BUG] x86 : i486 reporting to be vulnerable to Meltdown/Spectre_V1/Spectre_V2

From: Greg Kroah-Hartman
Date: Tue Feb 06 2018 - 14:02:45 EST


On Tue, Feb 06, 2018 at 01:33:30PM -0500, tedheadster wrote:
> On Sat, Feb 3, 2018 at 2:37 AM, David Woodhouse <dwmw2@xxxxxxxxxxxxx> wrote:
> > On Fri, 2018-02-02 at 23:52 -0500, tedheadster wrote:
> >> I just tested the 4.15 kernel and it is reporting that my old i486
> >> (non-cpuid capable) cpu is vulnerable to all three issues: Meltdown,
> >> Spectre V1, and Spectre V2.
> >>
> >> I find this to be _unlikely_.
> >
> > This should be fixed in Linus' tree already by commit fec9434a1
> > ("x86/pti: Do not enable PTI on CPUs which are not vulnerable to
> > Meltdown").
> >
> > We'll make sure it ends up in the stable tree too, if it hasn't
> > already.
>
> David
> I believe I got the patch(es) you mention in in the stable 4.15.1 kernel:
>
> Pull x86/pti updates from Thomas Gleixner: "Another set of melted
> spectrum related changes"
> (commit 6304672b7f0a5c010002e63a075160856dc4f88d).
>
> Unfortunately, the symptoms I reported remain on at least the i486 and i686.

Can you try 4.15.2-rc1? Or how about Linus's kernel tree now? There
was a lot of spectrum patches merged just this week that were not in
4.15.1.

thanks,

greg k-h