Since the advent of VGIC dynamic initialization, this latter is
initialized quite late on the first vcpu run or "on-demand", when
injecting an IRQ or when the guest sets its registers.
This series now allows the user space to explicitly request the VGIC init,
when the dimensioning parameters have been set: number of IRQs, number of
vCPUs. The target state is "initialized".
- the first patch file changes the error returned by vgic_init when no
online vcpu can be found.
- the second adds a new entry to the VGIC KVM device that allows
the user-space to manually request the VGIC init:
- a new KVM_DEV_ARM_VGIC_GRP_CTRL group is introduced.
- its first attribute is KVM_DEV_ARM_VGIC_CTRL_INIT
Applies on top of Christoffer's series:
"[PATCH v2 0/6] Fix vgic initialization problems"
- can be found at:
http://git.linaro.org/people/eric.auger/linux.git,
branch kvmarm-next-vgic-early-init-v3-official)
v2 -> v3:
- in KVM_DEV_ARM_VGIC_GRP_CTRL: vgic_init is called in place of former
kvm_vgic_init. Means this control moves the VGIC in initialized state
and not in ready state as before.
- "[PATCH v2 3/4] KVM: arm/arm64: check vgic_initialized before VCPU creation"
removed since included in Christoffer's
"arm/arm64: KVM: Don't allow creating VCPUs after vgic_initialized"
- [PATCH v2 4/4] KVM: arm/arm64: vgic: check vgic_initialized in
KVM_DEV_ARM_VGIC_GRP_ADDR removed since I noticed vgic_ioaddr_assign
would return -EEXIST in case vgic_map_resources were already been called.
- rewording in cover letter
v1 -> v2:
- 1, 3, 4 patch files added
- some rewording in vgic device documentation
Eric Auger (2):
KVM: arm/arm64: vgic: vgic_init returns -ENODEV when no online vcpu
KVM: arm/arm64: vgic: add init entry to VGIC KVM device
Documentation/virtual/kvm/devices/arm-vgic.txt | 11 +++++++++++
arch/arm/include/uapi/asm/kvm.h | 2 ++
arch/arm64/include/uapi/asm/kvm.h | 2 ++
virt/kvm/arm/vgic.c | 16 ++++++++++++++--
4 files changed, 29 insertions(+), 2 deletions(-)
--
1.9.1
To be more explicit on vgic initialization failure, -ENODEV is
returned by vgic_init when no online vcpus can be found at init.
Signed-off-by: Eric Auger <[email protected]>
---
v2 -> v3: vgic_init_maps was renamed into vgic_init
---
virt/kvm/arm/vgic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index e373b76..d61a61f 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -1809,7 +1809,7 @@ static int vgic_init(struct kvm *kvm)
nr_cpus = dist->nr_cpus = atomic_read(&kvm->online_vcpus);
if (!nr_cpus) /* No vcpus? Can't be good... */
- return -EINVAL;
+ return -ENODEV;
/*
* If nobody configured the number of interrupts, use the
--
1.9.1
Since the advent of VGIC dynamic initialization, this latter is
initialized quite late on the first vcpu run or "on-demand", when
injecting an IRQ or when the guest sets its registers.
This initialization could be initiated explicitly much earlier
by the users-space, as soon as it has provided the requested
dimensioning parameters.
This patch adds a new entry to the VGIC KVM device that allows
the user to manually request the VGIC init:
- a new KVM_DEV_ARM_VGIC_GRP_CTRL group is introduced.
- Its first attribute is KVM_DEV_ARM_VGIC_CTRL_INIT
The rationale behind introducing a group is to be able to add other
controls later on, if needed.
Signed-off-by: Eric Auger <[email protected]>
---
v2 -> v3:
- kvm_vgic_init replaced vgic_init. This means the target state now
is initialized and no more "ready"
v1 -> v2:
- some rewording in arm-vgic.txt and in the commit message
---
Documentation/virtual/kvm/devices/arm-vgic.txt | 11 +++++++++++
arch/arm/include/uapi/asm/kvm.h | 2 ++
arch/arm64/include/uapi/asm/kvm.h | 2 ++
virt/kvm/arm/vgic.c | 14 +++++++++++++-
4 files changed, 28 insertions(+), 1 deletion(-)
diff --git a/Documentation/virtual/kvm/devices/arm-vgic.txt b/Documentation/virtual/kvm/devices/arm-vgic.txt
index df8b0c7..30f5427 100644
--- a/Documentation/virtual/kvm/devices/arm-vgic.txt
+++ b/Documentation/virtual/kvm/devices/arm-vgic.txt
@@ -81,3 +81,14 @@ Groups:
-EINVAL: Value set is out of the expected range
-EBUSY: Value has already be set, or GIC has already been initialized
with default values.
+
+ KVM_DEV_ARM_VGIC_GRP_CTRL
+ Attributes:
+ KVM_DEV_ARM_VGIC_CTRL_INIT
+ request the initialization of the VGIC, no additional parameter in
+ kvm_device_attr.addr.
+ Errors:
+ -ENXIO: VGIC not properly configured as required prior to calling
+ this attribute
+ -ENODEV: no online VCPU
+ -ENOMEM: memory shortage when allocating vgic internal data
diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
index 09ee408..0db25bc 100644
--- a/arch/arm/include/uapi/asm/kvm.h
+++ b/arch/arm/include/uapi/asm/kvm.h
@@ -175,6 +175,8 @@ struct kvm_arch_memory_slot {
#define KVM_DEV_ARM_VGIC_OFFSET_SHIFT 0
#define KVM_DEV_ARM_VGIC_OFFSET_MASK (0xffffffffULL << KVM_DEV_ARM_VGIC_OFFSET_SHIFT)
#define KVM_DEV_ARM_VGIC_GRP_NR_IRQS 3
+#define KVM_DEV_ARM_VGIC_GRP_CTRL 4
+#define KVM_DEV_ARM_VGIC_CTRL_INIT 0
/* KVM_IRQ_LINE irq field index values */
#define KVM_ARM_IRQ_TYPE_SHIFT 24
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index 8e38878..480af34 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -161,6 +161,8 @@ struct kvm_arch_memory_slot {
#define KVM_DEV_ARM_VGIC_OFFSET_SHIFT 0
#define KVM_DEV_ARM_VGIC_OFFSET_MASK (0xffffffffULL << KVM_DEV_ARM_VGIC_OFFSET_SHIFT)
#define KVM_DEV_ARM_VGIC_GRP_NR_IRQS 3
+#define KVM_DEV_ARM_VGIC_GRP_CTRL 4
+#define KVM_DEV_ARM_VGIC_CTRL_INIT 0
/* KVM_IRQ_LINE irq field index values */
#define KVM_ARM_IRQ_TYPE_SHIFT 24
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index d61a61f..f7acda0 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -2302,7 +2302,14 @@ static int vgic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
return ret;
}
-
+ case KVM_DEV_ARM_VGIC_GRP_CTRL: {
+ switch (attr->attr) {
+ case KVM_DEV_ARM_VGIC_CTRL_INIT:
+ r = vgic_init(dev->kvm);
+ return r;
+ }
+ break;
+ }
}
return -ENXIO;
@@ -2381,6 +2388,11 @@ static int vgic_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr)
return vgic_has_attr_regs(vgic_cpu_ranges, offset);
case KVM_DEV_ARM_VGIC_GRP_NR_IRQS:
return 0;
+ case KVM_DEV_ARM_VGIC_GRP_CTRL:
+ switch (attr->attr) {
+ case KVM_DEV_ARM_VGIC_CTRL_INIT:
+ return 0;
+ }
}
return -ENXIO;
}
--
1.9.1