From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH] x86: kvm: use alternatives for VMCALL vs. VMMCALL if kernel text is read-only Date: Tue, 23 Sep 2014 10:27:28 +0200 Message-ID: <20140923082728.GC22072@pd.tnic> References: <1411384668-11135-1-git-send-email-pbonzini@redhat.com> <20140922194335.GB5119@pd.tnic> <5421288C.9090805@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, chris@arachsys.com, Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Borislav Petkov To: Paolo Bonzini Return-path: Content-Disposition: inline In-Reply-To: <5421288C.9090805@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On Tue, Sep 23, 2014 at 10:00:12AM +0200, Paolo Bonzini wrote: > 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. I see. Yeah, so the patch makes sense to me: Acked-by: Borislav Petkov Thanks. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --