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Date: Wed, 12 Jul 2017 15:47:06 +0200
From: Borislav Petkov <bp@alien8.de>
To: Mikulas Patocka <mpatocka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
        "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86/kernel/cpu/amd.c: don't apply the lahf_lm workaround
 in a hypervisor
Message-ID: <20170712134706.GA20584@nazgul.tnic>
References: <alpine.LRH.2.02.1707120318530.4739@file01.intranet.prod.int.rdu2.redhat.com>
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On Wed, Jul 12, 2017 at 03:19:56AM -0400, Mikulas Patocka wrote:
> When I start a virtual machine, kvm complains about accesses to an unknown
> MSR ("vcpu0 unhandled rdmsr: 0xc001100d"). This is caused by the code in
> init_amd_k8 that tries to work around a BIOS bug that incorrectly sets
> lahf_lm.

No need - there are a lot of qemu configurations which cause the
unhandled MSR warning so no need to pollute the kernel unnecessarily.
The warning is harmless at that.

-- 
Regards/Gruss,
    Boris.

ECO tip #101: Trim your mails when you reply.
--