Re: [PATCH 3/8] SVM: add module parameter to disable Nested Paging

Joerg Roedel
2008-01-25T22:10:29Z

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 <joerg.roedel-5C7GfCeVMHo@public.gmane.org>
> >---
> > 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

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