Re: [PATCH v3] Documentation: Add section about CPU vulnerabilities for Spectre
From: Thomas Gleixner
Date: Mon Jun 17 2019 - 16:28:57 EST
On Mon, 17 Jun 2019, Thomas Gleixner wrote:
> On Mon, 17 Jun 2019, Tim Chen wrote:
> > +Spectre variant 1 attacks take advantage of speculative execution of
> > +conditional branches, while Spectre variant 2 attacks use speculative
> > +execution of indirect branches to leak privileged memory. See  
> > +  .
> It would be great to actually link these [N] to the actual http link at the
> bottom. No idea what's the best way to do that.
> > +Mitigation control on the kernel command line
> > +---------------------------------------------
> > +
> > +Spectre variant 2 mitigation can be disabled or force enabled at the
> > +kernel command line.
> The below renders horribly when converted to HTML
> You probably want to wrap these into a table
> > + nospectre_v2 [X86] Disable all mitigations for the Spectre variant 2
> > + (indirect branch prediction) vulnerability. System may
> > + allow data leaks with this option, which is equivalent
> > + to spectre_v2=off.
> > +
> > +
> > + spectre_v2= [X86] Control mitigation of Spectre variant 2
> > + (indirect branch speculation) vulnerability.
> > + The default operation protects the kernel from
> > + user space attacks.
> Maybe Jonathan has a better idea.
But ideally you follow the table style which is used for the L1TF and MDS
command line options.