From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH] x86: kvm: use alternatives for VMCALL vs. VMMCALL if
 kernel text is read-only
Date: Tue, 23 Sep 2014 10:00:12 +0200
Message-ID: <5421288C.9090805@redhat.com>
References: <1411384668-11135-1-git-send-email-pbonzini@redhat.com> <20140922194335.GB5119@pd.tnic>
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Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	chris@arachsys.com, Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
	"H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
	Borislav Petkov <bp@suse.de>
To: Borislav Petkov <bp@alien8.de>
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <20140922194335.GB5119@pd.tnic>
Sender: linux-kernel-owner@vger.kernel.org
List-Id: kvm.vger.kernel.org

Il 22/09/2014 21:43, Borislav Petkov ha scritto:
>> > On x86_64, kernel text mappings are mapped read-only with CONFIG_DEBUG_RODATA.
> Hmm, that depends on DEBUG_KERNEL.
> 
> I think you're actually talking about distro kernels which enable
> CONFIG_DEBUG_RODATA, right?

This is for guest kernels, so it's not necessarily distro kernels.
Anyone who compiles their kernel with CONFIG_DEBUG_RODATA + PV spinlocks
would not be able to run it on AMD.

Paolo