From mboxrd@z Thu Jan 1 00:00:00 1970 From: christoffer.dall@linaro.org (Christoffer Dall) Date: Wed, 14 Aug 2013 13:43:02 -0700 Subject: [PATCH] KVM: ARM: ignore guest L2 cache control SMCs on Highbank and OMAP In-Reply-To: <520BE673.9010801@calxeda.com> References: <1376472125-23350-1-git-send-email-andre.przywara@calxeda.com> <520BE673.9010801@calxeda.com> Message-ID: <20130814204302.GA8837@cbox> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Aug 14, 2013 at 10:20:03PM +0200, Andre Przywara wrote: > On 08/14/2013 08:54 PM, Rob Herring wrote: > >On Wed, Aug 14, 2013 at 4:22 AM, Andre Przywara > > wrote: > >>Guest kernels with CONFIG_L2X0 set (for instance Highbank or OMAP4) > >>will trigger SMCs to handle the L2 cache controller (PL310). > >>This will currently inject #UNDEFs and eventually stop the guest. > >> > >>We don't need explicit L2 cache controller handling on A15s anymore, > >>so it is safe to simply ignore these calls and proceed with the next > >>instruction. > >> > >>Signed-off-by: Andre Przywara > >>--- > >> arch/arm/kvm/handle_exit.c | 20 ++++++++++++++++++++ > >> 1 file changed, 20 insertions(+) > > > >At least for highbank, we can fix this in the kernel: > > Yes, and we should do. But that won't fix older guest kernels, say > Ubuntu 12.10 or the like. And I think this is a use case for > virtualization, so we need both, guest and host fix. > Agreed, but we need a more generic solution for the secure call handling. I've created a backlog item in Linaro's JIRA (CARD-801) for this work, let's see how quickly we can get it approved and put on the roadmap. -Christoffer