It turns out that after some combination of header cleanups in upstream and refinements of this patch series and the other parts that are waiting in the wings to be sent next, we *can* get away with dropping the current Xen headers over the top of the existing partial set in include/hw/xen. We had previously added the new ones, done some cleanup to be able to use those, and then finally removed the old. But that isn't needed any more.
Also, now we have PV disk working correctly in the follow-on patches, we kind of want the guest not to think that its domain ID is zero; that gets confusing because QEMU itself is playing at being dom0. So default to 1 and also allow the --xen-domid to be set in an additional patch from Paul. As ever, a peek at what's to come *next* can be found in https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv There's a full XenStore implementation there, as well as the PV backend support for running in emulated mode that has been seen before. v10: https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv-kvm-10 • Move imported Xen headers to include/hw/xen/interface/. • Allow --xen-domid to be set, and default to non-zero. • Update documentation to include xen-evtchn-max-pirq and xen-gnttab-max-frames properties. • Explicitly include "qemu/lockable.h" in xen_evtchn.c to fix build. v9: https://lore.kernel.org/qemu-devel/20230128081113.1615111-1-dw...@infradead.org/ https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv-kvm-9 • Fix race in GSI deassertion. I still hate this and want to fix it to happen on EOI at the irqchip and fix VFIO too, but we can do that in a separate series rather than piling it into this one. At least this one is nicer than the VFIO one that already exists. • Fix user builds by not including xen-stubs.c in those. • On rebasing, add some explicit includes needed after header cleanups. v8: https://lore.kernel.org/qemu-devel/20230120131343.1441939-1-dw...@infradead.org/ https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv-kvm-8 • Instantiate xen pci-platform device automatically. • Add documentation. • Rename (newly-added) CONFIG_XENFV_PLATFORM to CONFIG_XEN_EMU. That's basically what it enables now that the dust is settling on the rest of the patch set that comes next. • Shift QMP commands to qapi/misc-target.json, other review feedback. • Clear upcall vector on soft reset. • Wire up soft reset to occur on qemu_devices_reset() (e.g. reboot). • Locking tweaks largely resulting from doing soft reset with the BQL. • Poll for deassertion of event channel GSI from kvm_arch_post_run() instead of kvm_arch_handle_exit(). • Add PIRQ support. v7: https://lore.kernel.org/qemu-devel/20230116215805.1123514-1-dw...@infradead.org/ https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv-kvm-7 • Trivial review feedback and collected ack/review tags. • Only call qemu_set_irq() under the BQL, which means doing so from a BH in some circumstances. v6: https://lore.kernel.org/qemu-devel/20230110122042.1562155-1-dw...@infradead.org/ https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv-kvm-6 • Require split irqchip to ensure the GSI handling works correctly. • Rework monitor commands to be QMP-based. • Cache vcpu_info hva to avoid MemoryRegion refcount leaks. • Pull in more Xen headers to allow for later PV backend work. • Define __XEN_TOOLS__ in hw/xen/xen.h instead of littering C files with separate definitions of __XEN_INTERFACE_VERSION__. • Drop debugging hexdump from xenstore processing. • Minor fixes in event channel backend handling. • Drop "Refactor xen_be_init()" patch. It turns out we're going to do that all quite differently, so it's neither necessary nor sufficient. v5: https://lore.kernel.org/qemu-devel/20221230121235.1282915-1-dw...@infradead.org/ https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv-kvm-5 • Add backend implementation of event channel support, to parallel the libxenevtchn API used by existing backend drivers. • Add basic XenStore ring implementation, test migration and kexec. • Some kexec/soft reset fixes (clear port pending bits, kernel timer virq). • Fix race with setting the xen_callback_asserted flag before actually doing so, which could lead to it being *cleared* again before we even assert it... and leave it asserted for ever. v4: https://lore.kernel.org/qemu-devel/20221221010623.1000191-1-dw...@infradead.org/ https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv-kvm-4 • Add soft reset support near the beginning and thread it through the rest of the feature enablement. • Add PV timer support and advertise XENFEAT_safe_hvm_pvclock. • Add basic grant table mapping and [gs]et_version / query_size support. • Make xen_platform device build (and work) without CONFIG_XEN. • Fix Xen HVM mode not to require --xen-attach. v3: https://lore.kernel.org/qemu-devel/20221216004117.862106-1-dw...@infradead.org/ https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv-kvm-3 • Switch back to xen-version as KVM accelerator property, other review feedback and bug fixes. • Fix Hyper-V coexistence (ick, calling kvm_xen_init() again because hyperv_enabled() doesn't return the right answer the first time). • Implement event channel support, including GSI/PCI_INTX callback. • Implement 32-bit guest support. v2: https://lore.kernel.org/qemu-devel/20221209095612.689243-1-dw...@infradead.org/ https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv-kvm-2 • Attempt to implement migration support; every Xen enlightenment is now recorded either from vmstate_x86_cpu or from a new sysdev device created for that purpose. And — I believe — correctly restored, in the right order, on vmload. • The shared_info page is created as a proper overlay instead of abusing the underlying guest page. This is important because Windows doesn't even select a GPA which had RAM behind it beforehand. This will be extended to handle the grant frames too, in the fullness of time. • Set vCPU attributes from the correct vCPU thread to avoid deadlocks. • Carefully copy the entire hypercall argument structure from userspace instead of assuming that it's contiguous in HVA space. • Distinguish between "handled but intentionally returns -ENOSYS" and "no idea what that was" in hypercalls, allowing us to emit a GUEST_ERROR (actually, shouldn't that change to UNIMP?) on the latter. Experience shows that to we'll end up having to intentionally return -ENOSYS to a bunch of weird crap that ancient guests still attempt to use, including XenServer local hacks that nobody even remembers what they were (hvmop 0x101, anyone? Some old Windows PV driver appears to be trying to use it...). * Drop the '+xen' CPU property and present Xen CPUID instead of KVM unconditionally when running in Xen mode. Make the Xen CPUID coexist with Hyper-V CPUID as it should, though. • Add XEN_EMU and XENFV_MACHINE (the latter to be XEN_EMU||XEN) config options. Some more work on this, and the incestuous relationships between the KVM target code and the 'platform' code, is going to be required but it's probably better to get on with implementing the real code so we can see those interactions in all their glory, before losing too much sleep over the details here. • Drop the GSI-2 hack, and also the patch which made the PCI platform device have real RAM (which isn't needed now we have overlays, qv). • Drop the XenState and XenVcpuState from KVMState and CPUArchState respectively. The Xen-specific fields are natively included in CPUArchState now though, for migration purposes. And we don't keep a host pointer to the shared_info or vcpu_info at all any more. With the kernel doing everything for us, we don't actually need them. v1: https://lore.kernel.org/qemu-devel/20221205173137.607044-1-dw...@infradead.org/ https://git.infradead.org/users/dwmw2/qemu.git/shortlog/refs/heads/xenfv-kvm-1 v0: https://github.com/jpemartins/qemu/commits/xen-shim-rfc (Joao et al.) Ankur Arora (2): i386/xen: implement HVMOP_set_evtchn_upcall_vector i386/xen: implement HVMOP_set_param David Woodhouse (39): xen: add CONFIG_XEN_BUS and CONFIG_XEN_EMU options for Xen emulation xen: Add XEN_DISABLED mode and make it default i386/kvm: Add xen-version KVM accelerator property and init KVM Xen support i386/hvm: Set Xen vCPU ID in KVM i386/xen: Implement SCHEDOP_poll and SCHEDOP_yield hw/xen: Add xen_overlay device for emulating shared xenheap pages i386/xen: add pc_machine_kvm_type to initialize XEN_EMULATE mode i386/xen: manage and save/restore Xen guest long_mode setting i386/xen: implement XENMEM_add_to_physmap_batch hw/xen: Add xen_evtchn device for event channel emulation i386/xen: Add support for Xen event channel delivery to vCPU hw/xen: Implement EVTCHNOP_status hw/xen: Implement EVTCHNOP_close hw/xen: Implement EVTCHNOP_unmask hw/xen: Implement EVTCHNOP_bind_virq hw/xen: Implement EVTCHNOP_bind_ipi hw/xen: Implement EVTCHNOP_send hw/xen: Implement EVTCHNOP_alloc_unbound hw/xen: Implement EVTCHNOP_bind_interdomain hw/xen: Implement EVTCHNOP_bind_vcpu hw/xen: Implement EVTCHNOP_reset hw/xen: Support HVM_PARAM_CALLBACK_TYPE_GSI callback hw/xen: Support HVM_PARAM_CALLBACK_TYPE_PCI_INTX callback kvm/i386: Add xen-gnttab-max-frames property hw/xen: Add xen_gnttab device for grant table emulation hw/xen: Support mapping grant frames i386/xen: Implement HYPERVISOR_grant_table_op and GNTTABOP_[gs]et_verson hw/xen: Implement GNTTABOP_query_size i386/xen: Reserve Xen special pages for console, xenstore rings hw/xen: Add backend implementation of interdomain event channel support hw/xen: Add xen_xenstore device for xenstore emulation hw/xen: Add basic ring handling to xenstore hw/xen: Automatically add xen-platform PCI device for emulated Xen guests i386/xen: Implement HYPERVISOR_physdev_op hw/xen: Implement emulated PIRQ hypercall support hw/xen: Support GSI mapping to PIRQ hw/xen: Support MSI mapping to PIRQ kvm/i386: Add xen-evtchn-max-pirq property i386/xen: Document Xen HVM emulation Joao Martins (17): include: import Xen public headers to hw/xen/interface i386/kvm: handle Xen HVM cpuid leaves xen-platform: exclude vfio-pci from the PCI platform unplug xen-platform: allow its creation with XEN_EMULATE mode i386/xen: handle guest hypercalls i386/xen: implement HYPERVISOR_xen_version i386/xen: implement HYPERVISOR_sched_op, SCHEDOP_shutdown i386/xen: implement HYPERVISOR_memory_op i386/xen: implement HYPERVISOR_hvm_op i386/xen: implement HYPERVISOR_vcpu_op i386/xen: handle VCPUOP_register_vcpu_info i386/xen: handle VCPUOP_register_vcpu_time_info i386/xen: handle VCPUOP_register_runstate_memory_area i386/xen: implement HYPERVISOR_event_channel_op i386/xen: add monitor commands to test event injection i386/xen: handle PV timer hypercalls i386/xen: handle HVMOP_get_param Paul Durrant (1): xen: Permit --xen-domid argument when accel is KVM accel/kvm/kvm-all.c | 3 + accel/xen/xen-all.c | 2 + docs/system/i386/xen.rst | 76 + docs/system/target-i386.rst | 1 + hmp-commands.hx | 29 + hw/Kconfig | 1 + hw/i386/Kconfig | 5 + hw/i386/kvm/meson.build | 13 + hw/i386/kvm/trace-events | 5 + hw/i386/kvm/trace.h | 1 + hw/i386/kvm/xen-stubs.c | 27 + hw/i386/kvm/xen_evtchn.c | 2330 ++++++++++++++++++++++++ hw/i386/kvm/xen_evtchn.h | 88 + hw/i386/kvm/xen_gnttab.c | 233 +++ hw/i386/kvm/xen_gnttab.h | 25 + hw/i386/kvm/xen_overlay.c | 272 +++ hw/i386/kvm/xen_overlay.h | 26 + hw/i386/kvm/xen_xenstore.c | 465 +++++ hw/i386/kvm/xen_xenstore.h | 20 + hw/i386/pc.c | 26 + hw/i386/x86.c | 16 + hw/i386/xen/meson.build | 5 +- hw/i386/xen/xen_platform.c | 57 +- hw/pci/msi.c | 11 + hw/pci/msix.c | 7 + hw/pci/pci.c | 17 + hw/xen/Kconfig | 3 + include/hw/i386/pc.h | 3 + include/hw/pci/msi.h | 1 + include/hw/xen/interface/arch-x86/cpuid.h | 118 ++ include/hw/xen/interface/arch-x86/xen-x86_32.h | 194 ++ include/hw/xen/interface/arch-x86/xen-x86_64.h | 241 +++ include/hw/xen/interface/arch-x86/xen.h | 398 ++++ include/hw/xen/interface/event_channel.h | 388 ++++ include/hw/xen/interface/features.h | 143 ++ include/hw/xen/interface/grant_table.h | 650 +++++++ include/hw/xen/interface/hvm/hvm_op.h | 395 ++++ include/hw/xen/interface/hvm/params.h | 318 ++++ include/hw/xen/interface/io/blkif.h | 14 +- include/hw/xen/interface/io/console.h | 10 + include/hw/xen/interface/io/fbif.h | 20 + include/hw/xen/interface/io/kbdif.h | 10 + include/hw/xen/interface/io/netif.h | 94 +- include/hw/xen/interface/io/ring.h | 99 +- include/hw/xen/interface/io/usbif.h | 377 ++-- include/hw/xen/interface/io/xenbus.h | 10 + include/hw/xen/interface/io/xs_wire.h | 153 ++ include/hw/xen/interface/memory.h | 754 ++++++++ include/hw/xen/interface/physdev.h | 383 ++++ include/hw/xen/interface/sched.h | 202 ++ include/hw/xen/interface/trace.h | 341 ++++ include/hw/xen/interface/vcpu.h | 248 +++ include/hw/xen/interface/version.h | 113 ++ include/hw/xen/interface/xen-compat.h | 46 + include/hw/xen/interface/xen.h | 1049 +++++++++++ include/hw/xen/xen.h | 21 +- include/monitor/hmp.h | 2 + include/sysemu/kvm_int.h | 4 + include/sysemu/kvm_xen.h | 42 + meson.build | 2 + qapi/misc-target.json | 116 ++ softmmu/globals.c | 2 +- softmmu/vl.c | 2 +- target/i386/cpu.c | 1 + target/i386/cpu.h | 19 + target/i386/kvm/kvm.c | 259 ++- target/i386/kvm/kvm_i386.h | 2 + target/i386/kvm/meson.build | 2 + target/i386/kvm/trace-events | 7 + target/i386/kvm/xen-compat.h | 70 + target/i386/kvm/xen-emu.c | 1867 +++++++++++++++++++ target/i386/kvm/xen-emu.h | 33 + target/i386/machine.c | 25 + 73 files changed, 12840 insertions(+), 172 deletions(-)
