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From:   Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Date:   Mon, 14 Aug 2023 03:30:51 +0500
Message-ID: <CABXGCsNSZD8GG1ZbpeNg54rjnsa9HQ3MumTgprLo8n5WE2VCoQ@mail.gmail.com>
Subject: Re: [regression/bisected] Add IBPB decreases performance in two times
To:     Borislav Petkov <bp@alien8.de>
Cc:     Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        x86@kernel.org
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On Sun, Aug 13, 2023 at 7:19=E2=80=AFPM Borislav Petkov <bp@alien8.de> wrot=
e:
> Nah, most people search the net and usually find the documentation, as
> past experience shows. In this case, they will find:
>
> https://kernel.org/doc/html/latest/admin-guide/hw-vuln/srso.html
>
> It will be there next week but here's the source:
>
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/D=
ocumentation/admin-guide/hw-vuln/srso.rst
>
> --
> Regards/Gruss,
>     Boris.
>
> https://people.kernel.org/tglx/notes-about-netiquette

I am figure out why I noticed lage impact of safe RET on my system.
safe-ret + KASAN =3D decrease performance for 50% in all scenarios
I use KASAN on a daily basis to catch bugs.
Is it possible for systems with KASAN to make a more optimal approach of SR=
SO?

--=20
Best Regards,
Mike Gavrilov.