On 31/07/15 13:59, Eric Auger wrote:

Hi Andre,
On 07/11/2015 01:17 AM, Andre Przywara wrote:

quoted

On 09/07/15 09:22, Eric Auger wrote:

quoted

If the ITS modality is not available, let's simply support MSI
injection by transforming the MSI.data into an SPI ID.

This becomes possible to use KVM_SIGNAL_MSI ioctl for arm too.

Signed-off-by: Eric Auger <redacted>

---

v1 -> v2:
- introduce vgic_v2m_inject_msi in vgic-v2-emul.c following Andre's
  advice
---
 arch/arm/kvm/Kconfig        |  1 +
 virt/kvm/arm/vgic-v2-emul.c | 12 ++++++++++++
 2 files changed, 13 insertions(+)

diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
index 151e710..0f58baf 100644
--- a/arch/arm/kvm/Kconfig
+++ b/arch/arm/kvm/Kconfig

@@ -31,6 +31,7 @@ config KVM
 	select KVM_VFIO
 	select HAVE_KVM_EVENTFD
 	select HAVE_KVM_IRQFD
+	select HAVE_KVM_MSI

I wonder if this requires some more code to only advertise
KVM_CAP_SIGNAL_MSI if userland actually sets up a GICv2M?
Otherwise userland could get the idea of being able to inectj MSIs
without the guest actually being prepared for that (because the GICv2M
driver did not initialize).

Not sure I get what you mean here. By directly transforming the user
provided MSI msg into an SPI ID, do we really have to care about GICv2M?

By user provided message you mean from user space? So this is an
emulated device, which the guest programs with an MSI payload and a
doorbell address at least? So how would a guest know these things
without having a MSI capable interrupt controller?

Or are we talking about different things here?

Cheers,
Andre.

Best Regards

Eric

quoted

Cheers,
Andre.

quoted

 	select HAVE_KVM_IRQCHIP
 	select HAVE_KVM_IRQ_ROUTING
 	depends on ARM_VIRT_EXT && ARM_LPAE && ARM_ARCH_TIMER

diff --git a/virt/kvm/arm/vgic-v2-emul.c b/virt/kvm/arm/vgic-v2-emul.c
index 1390797..43013cc 100644
--- a/virt/kvm/arm/vgic-v2-emul.c
+++ b/virt/kvm/arm/vgic-v2-emul.c

@@ -478,6 +478,17 @@ static bool vgic_v2_queue_sgi(struct kvm_vcpu *vcpu, int irq)
 }
 
 /**
+ * Emulates GICv2M MSI injection by injecting the SPI ID matching
+ * the msi data
+ * @kvm: pointer to the kvm struct
+ * @msi: the msi struct handle
+ */
+static int vgic_v2m_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
+{
+	return kvm_vgic_inject_irq(kvm, 0, msi->data, 1);
+}
+
+/**
  * kvm_vgic_map_resources - Configure global VGIC state before running any VCPUs
  * @kvm: pointer to the kvm struct
  *

@@ -566,6 +577,7 @@ void vgic_v2_init_emulation(struct kvm *kvm)
 	dist->vm_ops.add_sgi_source = vgic_v2_add_sgi_source;
 	dist->vm_ops.init_model = vgic_v2_init_model;
 	dist->vm_ops.map_resources = vgic_v2_map_resources;
+	dist->vm_ops.inject_msi = vgic_v2m_inject_msi;
 
 	kvm->arch.max_vcpus = VGIC_V2_MAX_CPUS;
 }