Re: [PATCH 3/3] Documentation/srso: Document IBPB aspect and fix formatting

From: Pawan Gupta
Date: Wed Aug 09 2023 - 18:03:39 EST


On Wed, Aug 09, 2023 at 12:27:00PM +0200, Borislav Petkov wrote:
> From: "Borislav Petkov (AMD)" <bp@xxxxxxxxx>
>
> Add a note about the dependency of the User->User mitigation on the
> previous Spectre v2 IBPB selection.
>
> Make the layout moar pretty.
>
> Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
> ---
> Documentation/admin-guide/hw-vuln/srso.rst | 71 ++++++++++++++--------
> 1 file changed, 44 insertions(+), 27 deletions(-)
>
> diff --git a/Documentation/admin-guide/hw-vuln/srso.rst b/Documentation/admin-guide/hw-vuln/srso.rst
> index 32eb5e6db272..af59a9395662 100644
> --- a/Documentation/admin-guide/hw-vuln/srso.rst
> +++ b/Documentation/admin-guide/hw-vuln/srso.rst
> @@ -42,42 +42,59 @@ The sysfs file showing SRSO mitigation status is:
>
> The possible values in this file are:
>
> - - 'Not affected' The processor is not vulnerable
> + * 'Not affected':
>
> - - 'Vulnerable: no microcode' The processor is vulnerable, no
> - microcode extending IBPB functionality
> - to address the vulnerability has been
> - applied.
> + The processor is not vulnerable
>
> - - 'Mitigation: microcode' Extended IBPB functionality microcode
> - patch has been applied. It does not
> - address User->Kernel and Guest->Host
> - transitions protection but it does
> - address User->User and VM->VM attack
> - vectors.
> + * 'Vulnerable: no microcode':

All other mitigations capitalizes the first letter, to be consistent
s/no microcode/No microcode/

> - (spec_rstack_overflow=microcode)
> + The processor is vulnerable, no microcode extending IBPB
> + functionality to address the vulnerability has been applied.
>
> - - 'Mitigation: safe RET' Software-only mitigation. It complements
> - the extended IBPB microcode patch
> - functionality by addressing User->Kernel
> - and Guest->Host transitions protection.
> + * 'Mitigation: microcode':

Ditto.