Merge branch 'xenfv-kvm-15' of git://git.infradead.org/users/dwmw2/qemu into HEAD

This adds support for emulating Xen under Linux/KVM, based on kernel
patches which have been present since Linux v5.12. As with the kernel
support, it's derived from work started by João Martins of Oracle in
2018.

This series just adds the basic platform support — CPUID, hypercalls,
event channels, a stub of XenStore.

A full single-tenant internal implementation of XenStore, and patches
to make QEMU's Xen PV drivers work with this Xen emulation, are waiting
in the wings to be submitted in a follow-on patch series.

As noted in the documentation, it's enabled by setting the xen-version
property on the KVM accelerator, e.g.:

 qemu-system-x86_64 -serial mon:stdio -M q35 -display none -m 1G -smp 2 \
    -accel kvm,xen-version=0x4000e,kernel-irqchip=split \
    -kernel vmlinuz-6.0.7-301.fc37.x86_64 \
    -append "console=ttyS0 root=/dev/sda1" \
    -drive file=/var/lib/libvirt/images/fedora28.qcow2,if=none,id=disk \
    -device ahci,id=ahci -device ide-hd,drive=disk,bus=ahci.0

Even before this was merged, we've already been using it to find and fix
bugs in the Linux kernel Xen guest support:

https://lore.kernel.org/all/4bffa69a949bfdc92c4a18e5a1c3cbb3b94a0d32.camel@infradead.org/
https://lore.kernel.org/all/871qnunycr.ffs@tglx/

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 5 insertions, 13 deletions

diff --git a/hw/isa/vt82c686.c b/hw/isa/vt82c686.c
index 3f9bd0c04d..f4c40965cd 100644
--- a/hw/isa/vt82c686.c
+++ b/hw/isa/vt82c686.c
@@ -548,9 +548,9 @@ OBJECT_DECLARE_SIMPLE_TYPE(ViaISAState, VIA_ISA)
 struct ViaISAState {
     PCIDevice dev;
     qemu_irq cpu_intr;
-    qemu_irq *isa_irqs;
+    qemu_irq *isa_irqs_in;
     ViaSuperIOState via_sio;
-    RTCState rtc;
+    MC146818RtcState rtc;
     PCIIDEState ide;
     UHCIState uhci[2];
     ViaPMState pm;
@@ -595,13 +595,7 @@ static const TypeInfo via_isa_info = {
 void via_isa_set_irq(PCIDevice *d, int n, int level)
 {
     ViaISAState *s = VIA_ISA(d);
-    qemu_set_irq(s->isa_irqs[n], level);
-}
-
-static void via_isa_request_i8259_irq(void *opaque, int irq, int level)
-{
-    ViaISAState *s = opaque;
-    qemu_set_irq(s->cpu_intr, level);
+    qemu_set_irq(s->isa_irqs_in[n], level);
 }
 
 static void via_isa_realize(PCIDevice *d, Error **errp)
@@ -609,12 +603,10 @@ static void via_isa_realize(PCIDevice *d, Error **errp)
     ViaISAState *s = VIA_ISA(d);
     DeviceState *dev = DEVICE(d);
     PCIBus *pci_bus = pci_get_bus(d);
-    qemu_irq *isa_irq;
     ISABus *isa_bus;
     int i;
 
     qdev_init_gpio_out(dev, &s->cpu_intr, 1);
-    isa_irq = qemu_allocate_irqs(via_isa_request_i8259_irq, s, 1);
     isa_bus = isa_bus_new(dev, pci_address_space(d), pci_address_space_io(d),
                           errp);
 
@@ -622,8 +614,8 @@ static void via_isa_realize(PCIDevice *d, Error **errp)
         return;
     }
 
-    s->isa_irqs = i8259_init(isa_bus, *isa_irq);
-    isa_bus_irqs(isa_bus, s->isa_irqs);
+    s->isa_irqs_in = i8259_init(isa_bus, s->cpu_intr);
+    isa_bus_register_input_irqs(isa_bus, s->isa_irqs_in);
     i8254_pit_init(isa_bus, 0x40, 0, NULL);
     i8257_dma_init(isa_bus, 0);