From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thiago Jung Bauermann Subject: [RFC PATCH 00/11] Secure Virtual Machine Enablement Date: Fri, 24 Aug 2018 13:25:24 -0300 Message-ID: <20180824162535.22798-1-bauerman@linux.ibm.com> Return-path: Sender: linux-kernel-owner@vger.kernel.org To: linuxppc-dev@lists.ozlabs.org Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Alexey Kardashevskiy , Anshuman Khandual , Benjamin Herrenschmidt , Christoph Hellwig , Michael Ellerman , Mike Anderson , Paul Mackerras , Ram Pai , Thiago Jung Bauermann List-Id: iommu@lists.linux-foundation.org [ Some people didn't receive all the patches in this series, even though the linuxppc-dev list did so trying to send again. This is exactly the same series I posted yesterday. Sorry for the clutter. ] This series contains preliminary work to enable Secure Virtual Machines (SVM) on powerpc. SVMs request to be migrated to secure memory very early in the boot process (in prom_init()), so by default all of their memory is inaccessible to the hypervisor. There is an ultravisor call that the VM can use to request certain pages to be made accessible (aka shared). The objective of these patches is to have the guest perform this request for buffers that need to be shared with the hypervisor, such as the LPPACAs, the SWIOTLB buffer and the Debug Trace Log. This work is incomplete: there are surely other memory regions that need to be made accessible, but I'm posting it early to get comments on whether the approach being taken is appropriate. It should be applied on top of the generic virtio DMA API rework series posted earlier, which adds a platform hook to override any arch based DMA API operations for any virtio device: https://lists.ozlabs.org/pipermail/linuxppc-dev/2018-July/175994.html I'm aware that changes need to be made to the patch series above, but IIUC it depends on upcoming virtio cleanup from Christoph Hellwig so for now the patch series above will be used as a stepping stone for this series. This code has been tested with virtio block, net and scsi devices with and without VIRTIO_F_IOMMU_PLATFORM flag. Please let me know what you think. For now I am testing on a regular guest with a couple of patches on top forcing is_svm_platform() to always return true and adding debug messages to confirm that mem_convert_shared() is being called in the expected places. These are the commands I'm using to start up the guest: Without VIRTIO_F_IOMMU_PLATFORM: qemu-system-ppc64 \ -enable-kvm \ -kernel /home/bauermann/src/linux/arch/powerpc/boot/zImage \ -append "root=PARTUUID=e550ad6f-05 ro" \ -machine pseries-2.6 \ -m 8G \ -smp 2 \ -serial mon:stdio \ -nographic \ -nodefaults \ -device virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x4 \ -drive file=/home/bauermann/VMs/svm.qcow2,format=qcow2,if=none,id=drive-scsi0-0-0-0 \ -device scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0 \ -drive file=/home/bauermann/VMs/svm-blk.qcow2,format=qcow2,if=none,id=drive-virtio-disk0 \ -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x5,drive=drive-virtio-disk0,id=virtio-disk0 \ -device virtio-net,netdev=hostnet0,id=net0,mac=52:54:00:96:70:1f \ -netdev user,id=hostnet0 \ -set netdev.hostnet0.hostfwd=tcp::42022-:22 With VIRTIO_F_IOMMU_PLATFORM. Same as above plus some -global options so that the virtio devices use the modern interface rather than the transitional one: qemu-system-ppc64 \ -enable-kvm \ -kernel /home/bauermann/src/linux/arch/powerpc/boot/zImage \ -append "root=PARTUUID=e550ad6f-05 ro" \ -machine pseries-2.6 \ -m 8G \ -smp 2 \ -serial mon:stdio \ -nographic \ -nodefaults \ -device virtio-scsi-pci,id=scsi0,bus=pci.0,addr=0x4 \ -drive file=/home/bauermann/VMs/svm.qcow2,format=qcow2,if=none,id=drive-scsi0-0-0-0 \ -device scsi-hd,bus=scsi0.0,channel=0,scsi-id=0,lun=0,drive=drive-scsi0-0-0-0,id=scsi0-0-0-0 \ -drive file=/home/bauermann/VMs/svm-blk.qcow2,format=qcow2,if=none,id=drive-virtio-disk0 \ -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x5,drive=drive-virtio-disk0,id=virtio-disk0 \ -device virtio-net,netdev=hostnet0,id=net0,mac=52:54:00:96:70:1f \ -netdev user,id=hostnet0 \ -set netdev.hostnet0.hostfwd=tcp::42022-:22 \ -global virtio-blk-pci.iommu_platform=true \ -global virtio-blk-pci.disable-legacy=on \ -global virtio-blk-pci.disable-modern=off \ -global virtio-net-pci.iommu_platform=true \ -global virtio-net-pci.disable-legacy=on \ -global virtio-net-pci.disable-modern=off \ -global virtio-scsi-pci.iommu_platform=true \ -global virtio-scsi-pci.disable-legacy=on \ -global virtio-scsi-pci.disable-modern=off The code was tested with a couple of other permutations where one virtio device has the flag VIRTIO_F_IOMMU_PLATFORM and others don't. Please suggest some other scenarios which need to be tested as well. Anshuman Khandual (10): powerpc/svm: Detect Secure Virtual Machine (SVM) platform powerpc/svm: Select CONFIG_DMA_DIRECT_OPS and CONFIG_SWIOTLB powerpc/svm: Add memory conversion (shared/secure) helper functions powerpc/svm: Convert SWIOTLB buffers to shared memory powerpc/svm: Don't release SWIOTLB buffers on secure guests powerpc/svm: Use SWIOTLB DMA API for all virtio devices powerpc/svm: Use shared memory for Debug Trace Log (DTL) powerpc/svm: Use shared memory for LPPACA structures powerpc/svm: Force the use of bounce buffers powerpc/svm: Increase SWIOTLB buffer size Thiago Jung Bauermann (1): powerpc: Add and use LPPACA_SIZE constant arch/powerpc/Kconfig | 22 ++++++++ arch/powerpc/include/asm/mem_encrypt.h | 19 +++++++ arch/powerpc/include/asm/reg.h | 3 ++ arch/powerpc/include/asm/svm.h | 26 +++++++++ arch/powerpc/kernel/Makefile | 1 + arch/powerpc/kernel/paca.c | 41 ++++++++++++-- arch/powerpc/kernel/svm.c | 99 ++++++++++++++++++++++++++++++++++ arch/powerpc/platforms/pseries/iommu.c | 6 ++- arch/powerpc/platforms/pseries/setup.c | 5 +- kernel/dma/swiotlb.c | 5 ++ 10 files changed, 221 insertions(+), 6 deletions(-) create mode 100644 arch/powerpc/include/asm/mem_encrypt.h create mode 100644 arch/powerpc/include/asm/svm.h create mode 100644 arch/powerpc/kernel/svm.c