Re: [patch V2 1/2] sysfs/cpu: Add vulnerability folder

From: Alan Cox
Date: Mon Jan 08 2018 - 06:55:13 EST


On Mon, 8 Jan 2018 08:35:14 +0300
Alexey Dobriyan <adobriyan@xxxxxxxxx> wrote:

> On Sun, Jan 07, 2018 at 10:50:58PM -0500, Konrad Rzeszutek Wilk wrote:
> > On Mon, Jan 08, 2018 at 01:22:04AM +0300, Alexey Dobriyan wrote:
> > > Thomas Gleixner wrote:
> > > > Create /sys/devices/system/cpu/vulnerabilities folder and files for
> > > > meltdown, spectre_v1 and spectre_v2.
> > >
> > > It is called "grep -e '^bugs' /proc/cpuinfo".
> > >
> > > kpti is deduceable from .config and /proc/cmdline .
> > > If people don't know what .config they are running, god bless them.
> >
> > It is not just for meltdown (kpti). You also have retpoline and IBRS
> > which is for spectre.
>
> If you, as kernel developer, are sure that bug is properly mitigated
> to the best of your knowledge then clear the bit from the bug mask.

It's probably useful to have the mitigation status somewhere because that
is what most people will care about. Both pieces of information are
needed though.

Alan