Re: /sys/devices/system/cpu/vulnerabilities/ doesn't show all known CPU vulnerabilities

[Thomas Gleixner]

On Wed, 14 Aug 2019, Kernel User wrote:
> On Wed, 14 Aug 2019 09:04:57 +0200 Borislav Petkov wrote:
> 
> > IMO, what you want does not belong in sysfs but in documentation.
> 
> How would documentation (a fixed static text file) tell whether a
> particular system is vulnerable or not?
> 
> > I partially see your point that a table of sorts mapping all those CPU
> > vulnerability names to (possible) mitigations is needed for users
> > which would like to know whether they're covered, without having to
> > run some scripts from github,
> 
> Correct.
> 
> > but sysfs just ain't the place.
> 
> Then why is it currently used for some of the vulnerabilities?

It's used to denote vulnerability classes and their mitigations:

  - Spectre v1
  - Spectre v2
  - Meltdown
  - SSB
  - L1TF
  - MDS

We are not tracking subclasses and their individual CVEs. The sysfs
interface is accurate (including SMT state) and the mapping to subclasses
and CVEs can be done by user space tools if required.

Thanks,

	tglx