Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Message-ID: <1516479485.9814.10.camel@amazon.co.uk>
Subject: Re: [RFC 02/10] x86/kvm: Add IBPB support
To:     KarimAllah Ahmed <karahmed@amazon.de>,
        <linux-kernel@vger.kernel.org>
CC:     Andi Kleen <ak@linux.intel.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Andy Lutomirski <luto@kernel.org>,
        Arjan van de Ven <arjan@linux.intel.com>,
        Ashok Raj <ashok.raj@intel.com>,
        Asit Mallick <asit.k.mallick@intel.com>,
        Borislav Petkov <bp@suse.de>,
        Dan Williams <dan.j.williams@intel.com>,
        "Dave Hansen" <dave.hansen@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "H . Peter Anvin" <hpa@zytor.com>, Ingo Molnar <mingo@redhat.com>,
        Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>,
        Joerg Roedel <joro@8bytes.org>,
        Jun Nakajima <jun.nakajima@intel.com>,
        Laura Abbott <labbott@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Radim =?UTF-8?Q?Kr=C4=8Dm=C3=A1=C5=99?= <rkrcmar@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        Tom Lendacky <thomas.lendacky@amd.com>, <kvm@vger.kernel.org>,
        <x86@kernel.org>, "Arjan Van De Ven" <arjan.van.de.ven@intel.com>
In-Reply-To: <1516476182-5153-3-git-send-email-karahmed@amazon.de>
References: <1516476182-5153-1-git-send-email-karahmed@amazon.de>
         <1516476182-5153-3-git-send-email-karahmed@amazon.de>
Face:   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
Organization: Amazon
Content-Type: multipart/signed; micalg=sha-256; protocol="application/x-pkcs7-signature"; boundary="=-PEYTPc0ZycZDjOOm88fF"
Date:   Sat, 20 Jan 2018 20:18:05 +0000
MIME-Version: 1.0
From:   "Woodhouse, David" <dwmw@amazon.co.uk>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

--=-PEYTPc0ZycZDjOOm88fF
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Sat, 2018-01-20 at 20:22 +0100, KarimAllah Ahmed wrote:
>=20
> @@ -6791,6 +6792,9 @@ static __init int hardware_setup(void)
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0kvm_tsc_scaling_ratio_frac_bits =3D 48;
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0}
> =C2=A0
> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0if (boot_cpu_has(X86_FEATURE_S=
PEC_CTRL))
> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0vmx_disable_intercept_for_msr(MSR_IA32_PRED_CMD, false);
> +

I've updated that to allow X86_FEATURE_AMD_PRED_CMD too, since some
hypervisors may expose *only* that MSR to guests even on Intel
hardware. PRED_CMD is a lot easier to expose as it doesn't need
storage, live migration support, and all that crap.

Our shared tree at
http://git.infradead.org/linux-retpoline.git/shortlog/refs/heads/ibpb
updated accordingly.


--=-PEYTPc0ZycZDjOOm88fF
Content-Type: application/x-pkcs7-signature; name="smime.p7s"
Content-Disposition: attachment; filename="smime.p7s"
Content-Transfer-Encoding: base64
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--=-PEYTPc0ZycZDjOOm88fF--