| Message ID | 1596478888-23030-1-git-send-email-olekstysh@gmail.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | IOREQ feature (+ virtio-mmio) on Arm | expand |
Hi Oleksandr, On 03/08/2020 19:21, Oleksandr Tyshchenko wrote: > From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> > > Hello all. > > The purpose of this patch series is to add IOREQ/DM support to Xen on Arm. > You can find an initial discussion at [1]. Xen on Arm requires some implementation > to forward guest MMIO access to a device model in order to implement virtio-mmio > backend or even mediator outside of hypervisor. As Xen on x86 already contains > required support this patch series tries to make it common and introduce Arm > specific bits plus some new functionality. Patch series is based on Julien's > PoC "xen/arm: Add support for Guest IO forwarding to a device emulator". > Besides splitting existing IOREQ/DM support and introducing Arm side, > the patch series also includes virtio-mmio related changes (toolstack) > for the reviewers to be able to see how the whole picture could look like. > For a non-RFC, the IOREQ/DM and virtio-mmio support will be sent separately. > > According to the initial discussion there are a few open questions/concerns > regarding security, performance in VirtIO solution: > 1. virtio-mmio vs virtio-pci, SPI vs MSI, different use-cases require different > transport... > 2. virtio backend is able to access all guest memory, some kind of protection > is needed: 'virtio-iommu in Xen' vs 'pre-shared-memory & memcpys in guest' > 3. interface between toolstack and 'out-of-qemu' virtio backend, avoid using > Xenstore in virtio backend if possible. > 4. a lot of 'foreing mapping' could lead to the memory exhaustion, Julien > has some idea regarding that. > > Looks like all of them are valid and worth considering, but the first thing > which we need on Arm is a mechanism to forward guest IO to a device emulator, > so let's focus on it in the first place. > > *** > > Patch series [2] was rebased on Xen v4.14 release and tested on Renesas Salvator-X > board + H3 ES3.0 SoC (Arm64) with virtio-mmio disk backend (we will share it later) > running in driver domain and unmodified Linux Guest running on existing > virtio-blk driver (frontend). No issues were observed. Guest domain 'reboot/destroy' > use-cases work properly. Patch series was only build-tested on x86. > > Please note, build-test passed for the following modes: > 1. x86: CONFIG_HVM=y / CONFIG_IOREQ_SERVER=y (default) > 2. x86: #CONFIG_HVM is not set / #CONFIG_IOREQ_SERVER is not set > 3. Arm64: CONFIG_HVM=y / CONFIG_IOREQ_SERVER=y (default) > 4. Arm64: CONFIG_HVM=y / #CONFIG_IOREQ_SERVER is not set > 5. Arm32: CONFIG_HVM=y / #CONFIG_IOREQ_SERVER is not set > > Build-test didn't pass for Arm32 mode with 'CONFIG_IOREQ_SERVER=y' due to the lack of > cmpxchg_64 support on Arm32. See cmpxchg usage in hvm_send_buffered_ioreq()). I have sent a patch to implement cmpxchg64() and guest_cmpxchg64() (see [1]). Cheers, [1] https://lore.kernel.org/xen-devel/20200815172143.1327-1-julien@xen.org/T/#u
On 15.08.20 20:24, Julien Grall wrote: > Hi Oleksandr, Hi Julien. > > On 03/08/2020 19:21, Oleksandr Tyshchenko wrote: >> From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> >> >> Hello all. >> >> The purpose of this patch series is to add IOREQ/DM support to Xen on >> Arm. >> You can find an initial discussion at [1]. Xen on Arm requires some >> implementation >> to forward guest MMIO access to a device model in order to implement >> virtio-mmio >> backend or even mediator outside of hypervisor. As Xen on x86 already >> contains >> required support this patch series tries to make it common and >> introduce Arm >> specific bits plus some new functionality. Patch series is based on >> Julien's >> PoC "xen/arm: Add support for Guest IO forwarding to a device emulator". >> Besides splitting existing IOREQ/DM support and introducing Arm side, >> the patch series also includes virtio-mmio related changes (toolstack) >> for the reviewers to be able to see how the whole picture could look >> like. >> For a non-RFC, the IOREQ/DM and virtio-mmio support will be sent >> separately. >> >> According to the initial discussion there are a few open >> questions/concerns >> regarding security, performance in VirtIO solution: >> 1. virtio-mmio vs virtio-pci, SPI vs MSI, different use-cases require >> different >> transport... >> 2. virtio backend is able to access all guest memory, some kind of >> protection >> is needed: 'virtio-iommu in Xen' vs 'pre-shared-memory & memcpys >> in guest' >> 3. interface between toolstack and 'out-of-qemu' virtio backend, >> avoid using >> Xenstore in virtio backend if possible. >> 4. a lot of 'foreing mapping' could lead to the memory exhaustion, >> Julien >> has some idea regarding that. >> >> Looks like all of them are valid and worth considering, but the first >> thing >> which we need on Arm is a mechanism to forward guest IO to a device >> emulator, >> so let's focus on it in the first place. >> >> *** >> >> Patch series [2] was rebased on Xen v4.14 release and tested on >> Renesas Salvator-X >> board + H3 ES3.0 SoC (Arm64) with virtio-mmio disk backend (we will >> share it later) >> running in driver domain and unmodified Linux Guest running on existing >> virtio-blk driver (frontend). No issues were observed. Guest domain >> 'reboot/destroy' >> use-cases work properly. Patch series was only build-tested on x86. >> >> Please note, build-test passed for the following modes: >> 1. x86: CONFIG_HVM=y / CONFIG_IOREQ_SERVER=y (default) >> 2. x86: #CONFIG_HVM is not set / #CONFIG_IOREQ_SERVER is not set >> 3. Arm64: CONFIG_HVM=y / CONFIG_IOREQ_SERVER=y (default) >> 4. Arm64: CONFIG_HVM=y / #CONFIG_IOREQ_SERVER is not set >> 5. Arm32: CONFIG_HVM=y / #CONFIG_IOREQ_SERVER is not set >> >> Build-test didn't pass for Arm32 mode with 'CONFIG_IOREQ_SERVER=y' >> due to the lack of >> cmpxchg_64 support on Arm32. See cmpxchg usage in >> hvm_send_buffered_ioreq()). > > I have sent a patch to implement cmpxchg64() and guest_cmpxchg64() > (see [1]). > > Cheers, > > [1] > https://lore.kernel.org/xen-devel/20200815172143.1327-1-julien@xen.org/T/#u Thank you! I have already build-tested it. No issues). I will update corresponding patch to select IOREQ_SERVER for "config ARM" instead of "config ARM64".
From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Hello all. The purpose of this patch series is to add IOREQ/DM support to Xen on Arm. You can find an initial discussion at [1]. Xen on Arm requires some implementation to forward guest MMIO access to a device model in order to implement virtio-mmio backend or even mediator outside of hypervisor. As Xen on x86 already contains required support this patch series tries to make it common and introduce Arm specific bits plus some new functionality. Patch series is based on Julien's PoC "xen/arm: Add support for Guest IO forwarding to a device emulator". Besides splitting existing IOREQ/DM support and introducing Arm side, the patch series also includes virtio-mmio related changes (toolstack) for the reviewers to be able to see how the whole picture could look like. For a non-RFC, the IOREQ/DM and virtio-mmio support will be sent separately. According to the initial discussion there are a few open questions/concerns regarding security, performance in VirtIO solution: 1. virtio-mmio vs virtio-pci, SPI vs MSI, different use-cases require different transport... 2. virtio backend is able to access all guest memory, some kind of protection is needed: 'virtio-iommu in Xen' vs 'pre-shared-memory & memcpys in guest' 3. interface between toolstack and 'out-of-qemu' virtio backend, avoid using Xenstore in virtio backend if possible. 4. a lot of 'foreing mapping' could lead to the memory exhaustion, Julien has some idea regarding that. Looks like all of them are valid and worth considering, but the first thing which we need on Arm is a mechanism to forward guest IO to a device emulator, so let's focus on it in the first place. *** Patch series [2] was rebased on Xen v4.14 release and tested on Renesas Salvator-X board + H3 ES3.0 SoC (Arm64) with virtio-mmio disk backend (we will share it later) running in driver domain and unmodified Linux Guest running on existing virtio-blk driver (frontend). No issues were observed. Guest domain 'reboot/destroy' use-cases work properly. Patch series was only build-tested on x86. Please note, build-test passed for the following modes: 1. x86: CONFIG_HVM=y / CONFIG_IOREQ_SERVER=y (default) 2. x86: #CONFIG_HVM is not set / #CONFIG_IOREQ_SERVER is not set 3. Arm64: CONFIG_HVM=y / CONFIG_IOREQ_SERVER=y (default) 4. Arm64: CONFIG_HVM=y / #CONFIG_IOREQ_SERVER is not set 5. Arm32: CONFIG_HVM=y / #CONFIG_IOREQ_SERVER is not set Build-test didn't pass for Arm32 mode with 'CONFIG_IOREQ_SERVER=y' due to the lack of cmpxchg_64 support on Arm32. See cmpxchg usage in hvm_send_buffered_ioreq()). *** Any feedback/help would be highly appreciated. [1] https://lists.xenproject.org/archives/html/xen-devel/2020-07/msg00825.html [2] https://github.com/otyshchenko1/xen/commits/ioreq_4.14_ml1 Oleksandr Tyshchenko (12): hvm/ioreq: Make x86's IOREQ feature common hvm/dm: Make x86's DM feature common xen/mm: Make x86's XENMEM_resource_ioreq_server handling common xen/arm: Introduce arch specific bits for IOREQ/DM features hvm/dm: Introduce xendevicemodel_set_irq_level DM op libxl: Introduce basic virtio-mmio support on Arm A collection of tweaks to be able to run emulator in driver domain xen/arm: Invalidate qemu mapcache on XENMEM_decrease_reservation libxl: Handle virtio-mmio irq in more correct way libxl: Add support for virtio-disk configuration libxl: Insert "dma-coherent" property into virtio-mmio device node libxl: Fix duplicate memory node in DT tools/libs/devicemodel/core.c | 18 + tools/libs/devicemodel/include/xendevicemodel.h | 4 + tools/libs/devicemodel/libxendevicemodel.map | 1 + tools/libxc/xc_dom_arm.c | 25 +- tools/libxl/Makefile | 4 +- tools/libxl/libxl_arm.c | 98 +- tools/libxl/libxl_create.c | 1 + tools/libxl/libxl_internal.h | 1 + tools/libxl/libxl_types.idl | 16 + tools/libxl/libxl_types_internal.idl | 1 + tools/libxl/libxl_virtio_disk.c | 109 ++ tools/xl/Makefile | 2 +- tools/xl/xl.h | 3 + tools/xl/xl_cmdtable.c | 15 + tools/xl/xl_parse.c | 116 ++ tools/xl/xl_virtio_disk.c | 46 + xen/arch/arm/Kconfig | 1 + xen/arch/arm/Makefile | 2 + xen/arch/arm/dm.c | 54 + xen/arch/arm/domain.c | 9 + xen/arch/arm/hvm.c | 46 +- xen/arch/arm/io.c | 67 +- xen/arch/arm/ioreq.c | 100 ++ xen/arch/arm/traps.c | 23 + xen/arch/x86/Kconfig | 1 + xen/arch/x86/hvm/dm.c | 289 +---- xen/arch/x86/hvm/emulate.c | 2 +- xen/arch/x86/hvm/hvm.c | 2 +- xen/arch/x86/hvm/io.c | 2 +- xen/arch/x86/hvm/ioreq.c | 1431 +---------------------- xen/arch/x86/hvm/stdvga.c | 2 +- xen/arch/x86/hvm/vmx/realmode.c | 1 + xen/arch/x86/hvm/vmx/vvmx.c | 2 +- xen/arch/x86/mm.c | 45 - xen/arch/x86/mm/shadow/common.c | 2 +- xen/common/Kconfig | 3 + xen/common/Makefile | 1 + xen/common/domain.c | 15 + xen/common/domctl.c | 8 +- xen/common/event_channel.c | 14 +- xen/common/hvm/Makefile | 2 + xen/common/hvm/dm.c | 288 +++++ xen/common/hvm/ioreq.c | 1430 ++++++++++++++++++++++ xen/common/memory.c | 54 +- xen/include/asm-arm/domain.h | 82 ++ xen/include/asm-arm/hvm/ioreq.h | 105 ++ xen/include/asm-arm/mm.h | 8 - xen/include/asm-arm/mmio.h | 1 + xen/include/asm-arm/p2m.h | 7 +- xen/include/asm-x86/hvm/ioreq.h | 45 +- xen/include/asm-x86/hvm/vcpu.h | 7 - xen/include/asm-x86/mm.h | 4 - xen/include/public/hvm/dm_op.h | 15 + xen/include/xen/hvm/ioreq.h | 89 ++ xen/include/xen/hypercall.h | 12 + xen/include/xsm/dummy.h | 20 +- xen/include/xsm/xsm.h | 6 +- xen/xsm/dummy.c | 2 +- xen/xsm/flask/hooks.c | 5 +- 59 files changed, 2958 insertions(+), 1806 deletions(-) create mode 100644 tools/libxl/libxl_virtio_disk.c create mode 100644 tools/xl/xl_virtio_disk.c create mode 100644 xen/arch/arm/dm.c create mode 100644 xen/arch/arm/ioreq.c create mode 100644 xen/common/hvm/Makefile create mode 100644 xen/common/hvm/dm.c create mode 100644 xen/common/hvm/ioreq.c create mode 100644 xen/include/asm-arm/hvm/ioreq.h create mode 100644 xen/include/xen/hvm/ioreq.h