From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Joerg Roedel" Subject: Re: [PATCH 3/8] SVM: add module parameter to disable Nested Paging Date: Fri, 25 Jan 2008 23:10:29 +0100 Message-ID: <20080125221029.GA23111@amd.com> References: <1201294393-22613-1-git-send-email-joerg.roedel@amd.com> <1201294393-22613-4-git-send-email-joerg.roedel@amd.com> <479A561B.8070009@codemonkey.ws> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Avi Kivity To: "Anthony Liguori" Return-path: In-Reply-To: <479A561B.8070009-rdkfGonbjUSkNkDKm+mE6A@public.gmane.org> Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org On Fri, Jan 25, 2008 at 03:35:23PM -0600, Anthony Liguori wrote: > Joerg Roedel wrote: > >To disable the use of the Nested Paging feature even if it is available in > >hardware this patch adds a module parameter. Nested Paging can be disabled by > >passing npt=off to the kvm_amd module. > > > >Signed-off-by: Joerg Roedel > >--- > > arch/x86/kvm/svm.c | 8 ++++++++ > > 1 files changed, 8 insertions(+), 0 deletions(-) > > > >diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c > >index 49bb57a..2e718ff 100644 > >--- a/arch/x86/kvm/svm.c > >+++ b/arch/x86/kvm/svm.c > >@@ -48,6 +48,9 @@ MODULE_LICENSE("GPL"); > > #define SVM_DEATURE_SVML (1 << 2) > > static bool npt_enabled = false; > >+static char *npt = "on"; > >+ > >+module_param(npt, charp, S_IRUGO); > > > > This would probably be better as an integer. Then we don't have to do nasty things like > implicitly cast a literal to a char *. Hmm, I used int for that first but typing npt=off seemed more userfriendly to me than npt=0. So I used char* for it. Joerg -- | AMD Saxony Limited Liability Company & Co. KG Operating | Wilschdorfer Landstr. 101, 01109 Dresden, Germany System | Register Court Dresden: HRA 4896 Research | General Partner authorized to represent: Center | AMD Saxony LLC (Wilmington, Delaware, US) | General Manager of AMD Saxony LLC: Dr. Hans-R. Deppe, Thomas McCoy ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/