RE: [PATCH 2/3] x86/speculation: Support Automatic IBRS

[David Laight]

From: Borislav Petkov
> Sent: 04 November 2022 21:52
> 
> On Fri, Nov 04, 2022 at 04:36:50PM -0500, Kim Phillips wrote:
> >  - Allow for spectre_v2=autoibrs in the kernel command line,
> >    reverting to auto-selection if the feature isn't available.
> 
> Why?
> 
> What the whole logic here should do is enable autoibrs when detected
> automatically, without the need for the user to even select it as it is
> the superior mitigation.

The only useful option is to allow a different option be
selected for code testing.
So maybe you want an option for completeness - for when
an 'even better' option is available.

	David

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