[RFC v2 00/12] KVM: arm/arm64: Allow multiple GICv3 redistributor regions

[RFC v2 00/12] KVM: arm/arm64: Allow multiple GICv3 redistributor regions

[Eric Auger]

At the moment the KVM VGICv3 only supports a single redistributor
region (whose base address is set through the GICv3 kvm device
KVM_DEV_ARM_VGIC_GRP_ADDR/KVM_VGIC_V3_ADDR_TYPE_REDIST). There,
all the redistributors are laid out contiguously. The size of this
single redistributor region is not set explicitly but instead
induced at a late stage by the number of online vcpus.

The GIC specification does not mandate all redistributors to be
contiguous. Moreover DT and ACPI were specified so that multiple
redistributors regions can be defined.

The current interface brings a limitation on QEMU where ARM
virt machine available GPA holes only allowed to assign a
redistributor region fitting a max of 123 vcpus. Overcoming this
limitation would force either to create a new machine or relocate
the single rdist region or allow the allocation of multiple rdist
regions.

This series enables this last alternative. A new GICv3 KVM device
KVM_DEV_ARM_VGIC_GRP_ADDR/KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION allows
to register individual redistributor regions whose size is defined
explicitly. Those rdist regions then are filled by vcpu rdist frames
according to the need. The vgic init and related base address checks
are impacted.

Best Regards

Eric

Git: complete series available at
https://github.com/eauger/linux/tree/4.16-rc7-rdist-regions-rfc-v2
Previous version:
https://github.com/eauger/linux/tree/v4.16-rc5-rdist-regions-rfc

History:
- Rework the uapi. Only bits [51:16] of the redist region are
  exposed. Also a new flags field was introduced
- Do not store the last bit in the vgic_cpu struct anymore
- remove dist->spis check in 1st patch
- add last patch to bump VGIC_V3_MAX_CPUS to 512
- advertise the new attribute

Eric Auger (12):
  KVM: arm/arm64: Set dist->spis to NULL after kfree
  KVM: arm/arm64: Document KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION
  KVM: arm/arm64: Replace the single rdist region by a list
  KVM: arm/arm64: Helper to locate free rdist index
  KVM: arm/arm64: Revisit Redistributor TYPER last bit computation
  KVM: arm/arm64: Helper to register a new redistributor region
  KVM: arm/arm64: Adapt vgic_v3_check_base to multiple rdist regions
  KVM: arm/arm64: Check vcpu redist base before registering an iodev
  KVM: arm/arm64: Check all vcpu redistributors are set on map_resources
  KVM: arm/arm64: Add KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION
  KVM: arm/arm64: Implement KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION
  KVM: arm/arm64: Bump VGIC_V3_MAX_CPUS to 512

 Documentation/virtual/kvm/devices/arm-vgic-v3.txt |  18 ++++
 arch/arm/include/uapi/asm/kvm.h                   |   7 +-
 arch/arm64/include/uapi/asm/kvm.h                 |   7 +-
 include/kvm/arm_vgic.h                            |  16 ++-
 virt/kvm/arm/vgic/vgic-init.c                     |  20 +++-
 virt/kvm/arm/vgic/vgic-kvm-device.c               |  53 +++++++++-
 virt/kvm/arm/vgic/vgic-mmio-v3.c                  | 116 +++++++++++++++++++---
 virt/kvm/arm/vgic/vgic-v3.c                       |  87 ++++++++++++----
 virt/kvm/arm/vgic/vgic.h                          |  34 ++++++-
 9 files changed, 308 insertions(+), 50 deletions(-)

-- 
2.5.5

[RFC v2 01/12] KVM: arm/arm64: Set dist->spis to NULL after kfree

[Eric Auger]

in case kvm_vgic_map_resources() fails, typically if the vgic
distributor is not defined, __kvm_vgic_destroy will be called
several times. Indeed kvm_vgic_map_resources() is called on
first vcpu run. As a result dist->spis is freeed more than once
and on the second time it causes a "kernel BUG at mm/slub.c:3912!"

Set dist->spis to NULL to avoid the crash.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 virt/kvm/arm/vgic/vgic-init.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 743ca5c..3349f2b 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -325,6 +325,7 @@ static void kvm_vgic_dist_destroy(struct kvm *kvm)
 	dist->initialized = false;
 
 	kfree(dist->spis);
+	dist->spis = NULL;
 	dist->nr_spis = 0;
 
 	if (vgic_supports_direct_msis(kvm))
-- 
2.5.5

[RFC v2 02/12] KVM: arm/arm64: Document KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION

[Eric Auger]

We introduce a new KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attribute in
KVM_DEV_ARM_VGIC_GRP_ADDR group. It allows userspace to provide the
base address and size of a redistributor region

Compared to KVM_VGIC_V3_ADDR_TYPE_REDIST, this new attribute allows
to declare several separate redistributor regions.

So the whole redist space does not need to be contiguous anymore.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 Documentation/virtual/kvm/devices/arm-vgic-v3.txt | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
index 9293b45..0ded904 100644
--- a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
+++ b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
@@ -27,6 +27,24 @@ Groups:
       VCPU and all of the redistributor pages are contiguous.
       Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
       This address needs to be 64K aligned.
+
+    KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION (rw, 64-bit)
+      The attr field of kvm_device_attr encodes 3 values:
+      bits:     | 63   ....  52  |  51   ....   16 | 15 - 12  |11 - 0
+      values:   |     count      |       base      |  flags   | index
+      - index encodes the unique redistributor region index
+      - flags: reserved for future use, currently 0
+      - base field encodes bits [51:16] of the guest physical base address
+        of the first redistributor in the region. There are two 64K pages
+        for each VCPU and all of the redistributor pages are contiguous
+        within the redistributor region.
+      - count encodes the number of redistributors in the region.
+      Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
+
+  It is invalid to mix calls with KVM_VGIC_V3_ADDR_TYPE_REDIST and
+  KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attributes. When attempted an
+  -EINVAL error is returned.
+
   Errors:
     -E2BIG:  Address outside of addressable IPA range
     -EINVAL: Incorrectly aligned address
-- 
2.5.5

[RFC v2 03/12] KVM: arm/arm64: Replace the single rdist region by a list

[Eric Auger]

At the moment KVM supports a single rdist region. We want to
support several separate rdist regions so let's introduce a list
of them. This patch currently only cares about a single
entry in this list as the functionality to register several redist
regions is not yet there. So this only translates the existing code
into something functionally similar using that new data struct.

The redistributor region handle is stored in the vgic_cpu structure
to allow later computation of the TYPER last bit.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 include/kvm/arm_vgic.h              | 14 +++++++++----
 virt/kvm/arm/vgic/vgic-init.c       | 16 ++++++++++++--
 virt/kvm/arm/vgic/vgic-kvm-device.c | 13 ++++++++++--
 virt/kvm/arm/vgic/vgic-mmio-v3.c    | 42 ++++++++++++++++++++++++++++---------
 virt/kvm/arm/vgic/vgic-v3.c         | 20 +++++++++++-------
 5 files changed, 79 insertions(+), 26 deletions(-)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 02924ae..64994d0 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -196,6 +196,14 @@ struct vgic_its {
 
 struct vgic_state_iter;
 
+struct vgic_redist_region {
+	uint32_t index;
+	gpa_t base;
+	uint32_t count; /* number of redistributors or 0 if single region */
+	uint32_t free_index; /* index of the next free redistributor */
+	struct list_head list;
+};
+
 struct vgic_dist {
 	bool			in_kernel;
 	bool			ready;
@@ -219,10 +227,7 @@ struct vgic_dist {
 		/* either a GICv2 CPU interface */
 		gpa_t			vgic_cpu_base;
 		/* or a number of GICv3 redistributor regions */
-		struct {
-			gpa_t		vgic_redist_base;
-			gpa_t		vgic_redist_free_offset;
-		};
+		struct list_head rd_regions;
 	};
 
 	/* distributor enabled */
@@ -312,6 +317,7 @@ struct vgic_cpu {
 	 */
 	struct vgic_io_device	rd_iodev;
 	struct vgic_io_device	sgi_iodev;
+	struct vgic_redist_region *rdreg;
 
 	/* Contains the attributes and gpa of the LPI pending tables. */
 	u64 pendbaser;
diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 3349f2b..ef509e6 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -173,8 +173,11 @@ int kvm_vgic_create(struct kvm *kvm, u32 type)
 	kvm->arch.vgic.vctrl_base = kvm_vgic_global_state.vctrl_base;
 
 	kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;
-	kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
-	kvm->arch.vgic.vgic_redist_base = VGIC_ADDR_UNDEF;
+
+	if (type == KVM_DEV_TYPE_ARM_VGIC_V2)
+		kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
+	else
+		INIT_LIST_HEAD(&kvm->arch.vgic.rd_regions);
 
 out_unlock:
 	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
@@ -320,6 +323,7 @@ int vgic_init(struct kvm *kvm)
 static void kvm_vgic_dist_destroy(struct kvm *kvm)
 {
 	struct vgic_dist *dist = &kvm->arch.vgic;
+	struct vgic_redist_region *rdreg, *next;
 
 	dist->ready = false;
 	dist->initialized = false;
@@ -328,6 +332,14 @@ static void kvm_vgic_dist_destroy(struct kvm *kvm)
 	dist->spis = NULL;
 	dist->nr_spis = 0;
 
+	if (kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
+		list_for_each_entry_safe(rdreg, next, &dist->rd_regions, list) {
+			list_del(&rdreg->list);
+			kfree(rdreg);
+		}
+		INIT_LIST_HEAD(&dist->rd_regions);
+	}
+
 	if (vgic_supports_direct_msis(kvm))
 		vgic_v4_teardown(kvm);
 }
diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
index 10ae6f3..e7b5a86 100644
--- a/virt/kvm/arm/vgic/vgic-kvm-device.c
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -66,6 +66,7 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
 	int r = 0;
 	struct vgic_dist *vgic = &kvm->arch.vgic;
 	phys_addr_t *addr_ptr, alignment;
+	uint64_t undef_value = VGIC_ADDR_UNDEF;
 
 	mutex_lock(&kvm->lock);
 	switch (type) {
@@ -84,7 +85,9 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
 		addr_ptr = &vgic->vgic_dist_base;
 		alignment = SZ_64K;
 		break;
-	case KVM_VGIC_V3_ADDR_TYPE_REDIST:
+	case KVM_VGIC_V3_ADDR_TYPE_REDIST: {
+		struct vgic_redist_region *rdreg;
+
 		r = vgic_check_type(kvm, KVM_DEV_TYPE_ARM_VGIC_V3);
 		if (r)
 			break;
@@ -92,8 +95,14 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
 			r = vgic_v3_set_redist_base(kvm, *addr);
 			goto out;
 		}
-		addr_ptr = &vgic->vgic_redist_base;
+		rdreg = list_first_entry(&vgic->rd_regions,
+					 struct vgic_redist_region, list);
+		if (!rdreg)
+			addr_ptr = &undef_value;
+		else
+			addr_ptr = &rdreg->base;
 		break;
+	}
 	default:
 		r = -ENODEV;
 	}
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 671fe81..d1aab18 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -580,8 +580,10 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 {
 	struct kvm *kvm = vcpu->kvm;
 	struct vgic_dist *vgic = &kvm->arch.vgic;
+	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
 	struct vgic_io_device *rd_dev = &vcpu->arch.vgic_cpu.rd_iodev;
 	struct vgic_io_device *sgi_dev = &vcpu->arch.vgic_cpu.sgi_iodev;
+	struct vgic_redist_region *rdreg;
 	gpa_t rd_base, sgi_base;
 	int ret;
 
@@ -591,13 +593,17 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 	 * function for all VCPUs when the base address is set.  Just return
 	 * without doing any work for now.
 	 */
-	if (IS_VGIC_ADDR_UNDEF(vgic->vgic_redist_base))
+	rdreg = list_first_entry(&vgic->rd_regions,
+				 struct vgic_redist_region, list);
+	if (!rdreg)
 		return 0;
 
 	if (!vgic_v3_check_base(kvm))
 		return -EINVAL;
 
-	rd_base = vgic->vgic_redist_base + vgic->vgic_redist_free_offset;
+	vgic_cpu->rdreg = rdreg;
+
+	rd_base = rdreg->base + rdreg->free_index * KVM_VGIC_V3_REDIST_SIZE;
 	sgi_base = rd_base + SZ_64K;
 
 	kvm_iodevice_init(&rd_dev->dev, &kvm_io_gic_ops);
@@ -631,7 +637,7 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 		goto out;
 	}
 
-	vgic->vgic_redist_free_offset += 2 * SZ_64K;
+	rdreg->free_index++;
 out:
 	mutex_unlock(&kvm->slots_lock);
 	return ret;
@@ -673,19 +679,31 @@ static int vgic_register_all_redist_iodevs(struct kvm *kvm)
 int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
 {
 	struct vgic_dist *vgic = &kvm->arch.vgic;
+	struct vgic_redist_region *rdreg;
 	int ret;
 
 	/* vgic_check_ioaddr makes sure we don't do this twice */
-	ret = vgic_check_ioaddr(kvm, &vgic->vgic_redist_base, addr, SZ_64K);
-	if (ret)
-		return ret;
-
-	vgic->vgic_redist_base = addr;
-	if (!vgic_v3_check_base(kvm)) {
-		vgic->vgic_redist_base = VGIC_ADDR_UNDEF;
+	if (!list_empty(&vgic->rd_regions))
 		return -EINVAL;
+
+	rdreg = kzalloc(sizeof(*rdreg), GFP_KERNEL);
+	if (!rdreg)
+		return -ENOMEM;
+
+	rdreg->base = VGIC_ADDR_UNDEF;
+
+	ret = vgic_check_ioaddr(kvm, &rdreg->base, addr, SZ_64K);
+	if (ret)
+		goto out;
+
+	rdreg->base = addr;
+	if (!vgic_v3_check_base(kvm)) {
+		ret = -EINVAL;
+		goto out;
 	}
 
+	list_add(&rdreg->list, &vgic->rd_regions);
+
 	/*
 	 * Register iodevs for each existing VCPU.  Adding more VCPUs
 	 * afterwards will register the iodevs when needed.
@@ -695,6 +713,10 @@ int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
 		return ret;
 
 	return 0;
+
+out:
+	kfree(rdreg);
+	return ret;
 }
 
 int vgic_v3_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr)
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 0ff2006..7e696e6 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -412,6 +412,9 @@ bool vgic_v3_check_base(struct kvm *kvm)
 {
 	struct vgic_dist *d = &kvm->arch.vgic;
 	gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;
+	struct vgic_redist_region *rdreg =
+		list_first_entry(&d->rd_regions,
+				 struct vgic_redist_region, list);
 
 	redist_size *= atomic_read(&kvm->online_vcpus);
 
@@ -419,18 +422,17 @@ bool vgic_v3_check_base(struct kvm *kvm)
 	    d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
 		return false;
 
-	if (!IS_VGIC_ADDR_UNDEF(d->vgic_redist_base) &&
-	    d->vgic_redist_base + redist_size < d->vgic_redist_base)
+	if (rdreg && (rdreg->base + redist_size < rdreg->base))
 		return false;
 
 	/* Both base addresses must be set to check if they overlap */
-	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) ||
-	    IS_VGIC_ADDR_UNDEF(d->vgic_redist_base))
+	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) || !rdreg)
 		return true;
 
-	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= d->vgic_redist_base)
+	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= rdreg->base)
 		return true;
-	if (d->vgic_redist_base + redist_size <= d->vgic_dist_base)
+
+	if (rdreg->base + redist_size <= d->vgic_dist_base)
 		return true;
 
 	return false;
@@ -440,12 +442,14 @@ int vgic_v3_map_resources(struct kvm *kvm)
 {
 	int ret = 0;
 	struct vgic_dist *dist = &kvm->arch.vgic;
+	struct vgic_redist_region *rdreg =
+		list_first_entry(&dist->rd_regions,
+				 struct vgic_redist_region, list);
 
 	if (vgic_ready(kvm))
 		goto out;
 
-	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) ||
-	    IS_VGIC_ADDR_UNDEF(dist->vgic_redist_base)) {
+	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) || !rdreg) {
 		kvm_err("Need to set vgic distributor addresses first\n");
 		ret = -ENXIO;
 		goto out;
-- 
2.5.5

[RFC v2 03/12] KVM: arm/arm64: Replace the single rdist region by a list

[Eric Auger]

At the moment KVM supports a single rdist region. We want to
support several separate rdist regions so let's introduce a list
of them. This patch currently only cares about a single
entry in this list as the functionality to register several redist
regions is not yet there. So this only translates the existing code
into something functionally similar using that new data struct.

The redistributor region handle is stored in the vgic_cpu structure
to allow later computation of the TYPER last bit.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 include/kvm/arm_vgic.h              | 14 +++++++++----
 virt/kvm/arm/vgic/vgic-init.c       | 16 ++++++++++++--
 virt/kvm/arm/vgic/vgic-kvm-device.c | 13 ++++++++++--
 virt/kvm/arm/vgic/vgic-mmio-v3.c    | 42 ++++++++++++++++++++++++++++---------
 virt/kvm/arm/vgic/vgic-v3.c         | 20 +++++++++++-------
 5 files changed, 79 insertions(+), 26 deletions(-)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 02924ae..64994d0 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -196,6 +196,14 @@ struct vgic_its {
 
 struct vgic_state_iter;
 
+struct vgic_redist_region {
+	uint32_t index;
+	gpa_t base;
+	uint32_t count; /* number of redistributors or 0 if single region */
+	uint32_t free_index; /* index of the next free redistributor */
+	struct list_head list;
+};
+
 struct vgic_dist {
 	bool			in_kernel;
 	bool			ready;
@@ -219,10 +227,7 @@ struct vgic_dist {
 		/* either a GICv2 CPU interface */
 		gpa_t			vgic_cpu_base;
 		/* or a number of GICv3 redistributor regions */
-		struct {
-			gpa_t		vgic_redist_base;
-			gpa_t		vgic_redist_free_offset;
-		};
+		struct list_head rd_regions;
 	};
 
 	/* distributor enabled */
@@ -312,6 +317,7 @@ struct vgic_cpu {
 	 */
 	struct vgic_io_device	rd_iodev;
 	struct vgic_io_device	sgi_iodev;
+	struct vgic_redist_region *rdreg;
 
 	/* Contains the attributes and gpa of the LPI pending tables. */
 	u64 pendbaser;
diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 3349f2b..ef509e6 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -173,8 +173,11 @@ int kvm_vgic_create(struct kvm *kvm, u32 type)
 	kvm->arch.vgic.vctrl_base = kvm_vgic_global_state.vctrl_base;
 
 	kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;
-	kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
-	kvm->arch.vgic.vgic_redist_base = VGIC_ADDR_UNDEF;
+
+	if (type == KVM_DEV_TYPE_ARM_VGIC_V2)
+		kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
+	else
+		INIT_LIST_HEAD(&kvm->arch.vgic.rd_regions);
 
 out_unlock:
 	for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) {
@@ -320,6 +323,7 @@ int vgic_init(struct kvm *kvm)
 static void kvm_vgic_dist_destroy(struct kvm *kvm)
 {
 	struct vgic_dist *dist = &kvm->arch.vgic;
+	struct vgic_redist_region *rdreg, *next;
 
 	dist->ready = false;
 	dist->initialized = false;
@@ -328,6 +332,14 @@ static void kvm_vgic_dist_destroy(struct kvm *kvm)
 	dist->spis = NULL;
 	dist->nr_spis = 0;
 
+	if (kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) {
+		list_for_each_entry_safe(rdreg, next, &dist->rd_regions, list) {
+			list_del(&rdreg->list);
+			kfree(rdreg);
+		}
+		INIT_LIST_HEAD(&dist->rd_regions);
+	}
+
 	if (vgic_supports_direct_msis(kvm))
 		vgic_v4_teardown(kvm);
 }
diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
index 10ae6f3..e7b5a86 100644
--- a/virt/kvm/arm/vgic/vgic-kvm-device.c
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -66,6 +66,7 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
 	int r = 0;
 	struct vgic_dist *vgic = &kvm->arch.vgic;
 	phys_addr_t *addr_ptr, alignment;
+	uint64_t undef_value = VGIC_ADDR_UNDEF;
 
 	mutex_lock(&kvm->lock);
 	switch (type) {
@@ -84,7 +85,9 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
 		addr_ptr = &vgic->vgic_dist_base;
 		alignment = SZ_64K;
 		break;
-	case KVM_VGIC_V3_ADDR_TYPE_REDIST:
+	case KVM_VGIC_V3_ADDR_TYPE_REDIST: {
+		struct vgic_redist_region *rdreg;
+
 		r = vgic_check_type(kvm, KVM_DEV_TYPE_ARM_VGIC_V3);
 		if (r)
 			break;
@@ -92,8 +95,14 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
 			r = vgic_v3_set_redist_base(kvm, *addr);
 			goto out;
 		}
-		addr_ptr = &vgic->vgic_redist_base;
+		rdreg = list_first_entry(&vgic->rd_regions,
+					 struct vgic_redist_region, list);
+		if (!rdreg)
+			addr_ptr = &undef_value;
+		else
+			addr_ptr = &rdreg->base;
 		break;
+	}
 	default:
 		r = -ENODEV;
 	}
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 671fe81..d1aab18 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -580,8 +580,10 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 {
 	struct kvm *kvm = vcpu->kvm;
 	struct vgic_dist *vgic = &kvm->arch.vgic;
+	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
 	struct vgic_io_device *rd_dev = &vcpu->arch.vgic_cpu.rd_iodev;
 	struct vgic_io_device *sgi_dev = &vcpu->arch.vgic_cpu.sgi_iodev;
+	struct vgic_redist_region *rdreg;
 	gpa_t rd_base, sgi_base;
 	int ret;
 
@@ -591,13 +593,17 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 	 * function for all VCPUs when the base address is set.  Just return
 	 * without doing any work for now.
 	 */
-	if (IS_VGIC_ADDR_UNDEF(vgic->vgic_redist_base))
+	rdreg = list_first_entry(&vgic->rd_regions,
+				 struct vgic_redist_region, list);
+	if (!rdreg)
 		return 0;
 
 	if (!vgic_v3_check_base(kvm))
 		return -EINVAL;
 
-	rd_base = vgic->vgic_redist_base + vgic->vgic_redist_free_offset;
+	vgic_cpu->rdreg = rdreg;
+
+	rd_base = rdreg->base + rdreg->free_index * KVM_VGIC_V3_REDIST_SIZE;
 	sgi_base = rd_base + SZ_64K;
 
 	kvm_iodevice_init(&rd_dev->dev, &kvm_io_gic_ops);
@@ -631,7 +637,7 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 		goto out;
 	}
 
-	vgic->vgic_redist_free_offset += 2 * SZ_64K;
+	rdreg->free_index++;
 out:
 	mutex_unlock(&kvm->slots_lock);
 	return ret;
@@ -673,19 +679,31 @@ static int vgic_register_all_redist_iodevs(struct kvm *kvm)
 int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
 {
 	struct vgic_dist *vgic = &kvm->arch.vgic;
+	struct vgic_redist_region *rdreg;
 	int ret;
 
 	/* vgic_check_ioaddr makes sure we don't do this twice */
-	ret = vgic_check_ioaddr(kvm, &vgic->vgic_redist_base, addr, SZ_64K);
-	if (ret)
-		return ret;
-
-	vgic->vgic_redist_base = addr;
-	if (!vgic_v3_check_base(kvm)) {
-		vgic->vgic_redist_base = VGIC_ADDR_UNDEF;
+	if (!list_empty(&vgic->rd_regions))
 		return -EINVAL;
+
+	rdreg = kzalloc(sizeof(*rdreg), GFP_KERNEL);
+	if (!rdreg)
+		return -ENOMEM;
+
+	rdreg->base = VGIC_ADDR_UNDEF;
+
+	ret = vgic_check_ioaddr(kvm, &rdreg->base, addr, SZ_64K);
+	if (ret)
+		goto out;
+
+	rdreg->base = addr;
+	if (!vgic_v3_check_base(kvm)) {
+		ret = -EINVAL;
+		goto out;
 	}
 
+	list_add(&rdreg->list, &vgic->rd_regions);
+
 	/*
 	 * Register iodevs for each existing VCPU.  Adding more VCPUs
 	 * afterwards will register the iodevs when needed.
@@ -695,6 +713,10 @@ int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
 		return ret;
 
 	return 0;
+
+out:
+	kfree(rdreg);
+	return ret;
 }
 
 int vgic_v3_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr)
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 0ff2006..7e696e6 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -412,6 +412,9 @@ bool vgic_v3_check_base(struct kvm *kvm)
 {
 	struct vgic_dist *d = &kvm->arch.vgic;
 	gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;
+	struct vgic_redist_region *rdreg =
+		list_first_entry(&d->rd_regions,
+				 struct vgic_redist_region, list);
 
 	redist_size *= atomic_read(&kvm->online_vcpus);
 
@@ -419,18 +422,17 @@ bool vgic_v3_check_base(struct kvm *kvm)
 	    d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
 		return false;
 
-	if (!IS_VGIC_ADDR_UNDEF(d->vgic_redist_base) &&
-	    d->vgic_redist_base + redist_size < d->vgic_redist_base)
+	if (rdreg && (rdreg->base + redist_size < rdreg->base))
 		return false;
 
 	/* Both base addresses must be set to check if they overlap */
-	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) ||
-	    IS_VGIC_ADDR_UNDEF(d->vgic_redist_base))
+	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) || !rdreg)
 		return true;
 
-	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= d->vgic_redist_base)
+	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= rdreg->base)
 		return true;
-	if (d->vgic_redist_base + redist_size <= d->vgic_dist_base)
+
+	if (rdreg->base + redist_size <= d->vgic_dist_base)
 		return true;
 
 	return false;
@@ -440,12 +442,14 @@ int vgic_v3_map_resources(struct kvm *kvm)
 {
 	int ret = 0;
 	struct vgic_dist *dist = &kvm->arch.vgic;
+	struct vgic_redist_region *rdreg =
+		list_first_entry(&dist->rd_regions,
+				 struct vgic_redist_region, list);
 
 	if (vgic_ready(kvm))
 		goto out;
 
-	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) ||
-	    IS_VGIC_ADDR_UNDEF(dist->vgic_redist_base)) {
+	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) || !rdreg) {
 		kvm_err("Need to set vgic distributor addresses first\n");
 		ret = -ENXIO;
 		goto out;
-- 
2.5.5

[RFC v2 04/12] KVM: arm/arm64: Helper to locate free rdist index

[Eric Auger]

We introduce vgic_v3_rdist_free_slot to help identifying
where we can place a new 2x64KB redistributor.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 virt/kvm/arm/vgic/vgic-mmio-v3.c |  3 +--
 virt/kvm/arm/vgic/vgic-v3.c      | 17 +++++++++++++++++
 virt/kvm/arm/vgic/vgic.h         | 11 +++++++++++
 3 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index d1aab18..49ca176 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -593,8 +593,7 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 	 * function for all VCPUs when the base address is set.  Just return
 	 * without doing any work for now.
 	 */
-	rdreg = list_first_entry(&vgic->rd_regions,
-				 struct vgic_redist_region, list);
+	rdreg = vgic_v3_rdist_free_slot(&vgic->rd_regions);
 	if (!rdreg)
 		return 0;
 
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 7e696e6..6a7e4065 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -438,6 +438,23 @@ bool vgic_v3_check_base(struct kvm *kvm)
 	return false;
 }
 
+/**
+ * vgic_v3_rdist_free_slot - Look up registered rdist regions and identify one
+ * which has free space to put a new rdist regions
+ *
+ * If any, return this redist region handle, otherwise returns NULL.
+ */
+struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rd_regions)
+{
+	struct vgic_redist_region *rdreg;
+
+	list_for_each_entry(rdreg, rd_regions, list) {
+		if (!vgic_v3_redist_region_full(rdreg))
+			return rdreg;
+	}
+	return NULL;
+}
+
 int vgic_v3_map_resources(struct kvm *kvm)
 {
 	int ret = 0;
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index f5b8519..d5e89b8 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -248,6 +248,17 @@ static inline int vgic_v3_max_apr_idx(struct kvm_vcpu *vcpu)
 	}
 }
 
+static inline bool
+vgic_v3_redist_region_full(struct vgic_redist_region *region)
+{
+	if (!region->count)
+		return false;
+
+	return (region->free_index >= region->count);
+}
+
+struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rdregs);
+
 int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its,
 			 u32 devid, u32 eventid, struct vgic_irq **irq);
 struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi);
-- 
2.5.5

[RFC v2 05/12] KVM: arm/arm64: Revisit Redistributor TYPER last bit computation

[Eric Auger]

The TYPER of an redistributor reflects whether the rdist is
the last one of the redistributor region. Let's compare the TYPER
GPA against the address of the last occupied slot within the
redistributor region.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 virt/kvm/arm/vgic/vgic-mmio-v3.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 49ca176..ce5c927 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -184,12 +184,17 @@ static unsigned long vgic_mmio_read_v3r_typer(struct kvm_vcpu *vcpu,
 					      gpa_t addr, unsigned int len)
 {
 	unsigned long mpidr = kvm_vcpu_get_mpidr_aff(vcpu);
+	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+	struct vgic_redist_region *rdreg = vgic_cpu->rdreg;
 	int target_vcpu_id = vcpu->vcpu_id;
+	gpa_t last_rdist_typer = rdreg->base + GICR_TYPER +
+			(rdreg->free_index - 1) * KVM_VGIC_V3_REDIST_SIZE;
 	u64 value;
 
 	value = (u64)(mpidr & GENMASK(23, 0)) << 32;
 	value |= ((target_vcpu_id & 0xffff) << 8);
-	if (target_vcpu_id == atomic_read(&vcpu->kvm->online_vcpus) - 1)
+
+	if (addr == last_rdist_typer)
 		value |= GICR_TYPER_LAST;
 	if (vgic_has_its(vcpu->kvm))
 		value |= GICR_TYPER_PLPIS;
-- 
2.5.5

[RFC v2 06/12] KVM: arm/arm64: Helper to register a new redistributor region

[Eric Auger]

We introduce a new helper that creates and inserts a new redistributor
region into the rdist region list. This helper both handles the case
where the redistributor region size is known at registration time
and the legacy case where it is not (eventually depending on the number
of online vcpus). Depending on pfns, we perform all the possible checks
that we can do:

- end of memory crossing
- incorrect alignment of the base address
- collision with distributor region if already defined
- collision with already registered rdist regions
- check of the new index

Rdist regions must be inserted by increasing order of indices. Indices
must be contiguous.

We also introduce vgic_v3_rdist_region_from_index() which will be used
from the vgic kvm-device, later on.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 virt/kvm/arm/vgic/vgic-mmio-v3.c | 91 +++++++++++++++++++++++++++++++++-------
 virt/kvm/arm/vgic/vgic-v3.c      | 29 +++++++++++++
 virt/kvm/arm/vgic/vgic.h         | 14 +++++++
 3 files changed, 118 insertions(+), 16 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index ce5c927..2f3b9e5 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -680,14 +680,62 @@ static int vgic_register_all_redist_iodevs(struct kvm *kvm)
 	return ret;
 }
 
-int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
+/**
+ * vgic_v3_insert_redist_region - Insert a new redistributor region
+ *
+ * Performs various checks before inserting the rdist region in the list.
+ * Those tests depend on whether the size of the rdist region is known
+ * (ie. count != 0). The list is sorted by rdist region index.
+ *
+ * @kvm: kvm handle
+ * @index: redist region index
+ * @base: base of the new rdist region
+ * @count: number of redistributors the region is made of (of 0 in the old style
+ * single region, whose size is induced from the number of vcpus)
+ *
+ * Return 0 on success, < 0 otherwise
+ */
+static int vgic_v3_insert_redist_region(struct kvm *kvm, uint32_t index,
+					gpa_t base, uint32_t count)
 {
-	struct vgic_dist *vgic = &kvm->arch.vgic;
+	struct vgic_dist *d = &kvm->arch.vgic;
 	struct vgic_redist_region *rdreg;
+	struct list_head *rd_regions = &d->rd_regions;
+	struct list_head *last = rd_regions->prev;
+
+	gpa_t new_start, new_end;
+	size_t size = count * KVM_VGIC_V3_REDIST_SIZE;
 	int ret;
 
-	/* vgic_check_ioaddr makes sure we don't do this twice */
-	if (!list_empty(&vgic->rd_regions))
+	/* single rdist region already set ?*/
+	if (!count && !list_empty(rd_regions))
+		return -EINVAL;
+
+	/* cross the end of memory ? */
+	if (base + size < base)
+		return -EINVAL;
+
+	if (list_empty(rd_regions)) {
+		if (index != 0)
+			return -EINVAL;
+	} else {
+		rdreg = list_entry(last, struct vgic_redist_region, list);
+		if (index != rdreg->index + 1)
+			return -EINVAL;
+	}
+
+	/*
+	 * collision with already set dist region ?
+	 * this assumes we know the size of the new rdist region (pfns != 0)
+	 * otherwise we can only test this when all vcpus are registered
+	 */
+	if (!count && !IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) &&
+		(!(d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= base)) &&
+		(!(base + size <= d->vgic_dist_base)))
+		return -EINVAL;
+
+	/* collision with any other rdist region? */
+	if (vgic_v3_rdist_overlap(kvm, base, size))
 		return -EINVAL;
 
 	rdreg = kzalloc(sizeof(*rdreg), GFP_KERNEL);
@@ -696,17 +744,32 @@ int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
 
 	rdreg->base = VGIC_ADDR_UNDEF;
 
-	ret = vgic_check_ioaddr(kvm, &rdreg->base, addr, SZ_64K);
+	ret = vgic_check_ioaddr(kvm, &rdreg->base, base, SZ_64K);
 	if (ret)
-		goto out;
+		goto free;
 
-	rdreg->base = addr;
-	if (!vgic_v3_check_base(kvm)) {
-		ret = -EINVAL;
-		goto out;
-	}
+	rdreg->base = base;
+	rdreg->count = count;
+	rdreg->free_index = 0;
+	rdreg->index = index;
 
-	list_add(&rdreg->list, &vgic->rd_regions);
+	new_start = base;
+	new_end = base + size - 1;
+
+	list_add_tail(&rdreg->list, rd_regions);
+	return 0;
+free:
+	kfree(rdreg);
+	return ret;
+}
+
+int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
+{
+	int ret;
+
+	ret = vgic_v3_insert_redist_region(kvm, 0, addr, 0);
+	if (ret)
+		return ret;
 
 	/*
 	 * Register iodevs for each existing VCPU.  Adding more VCPUs
@@ -717,10 +780,6 @@ int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
 		return ret;
 
 	return 0;
-
-out:
-	kfree(rdreg);
-	return ret;
 }
 
 int vgic_v3_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr)
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 6a7e4065..9a19129 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -404,6 +404,21 @@ int vgic_v3_save_pending_tables(struct kvm *kvm)
 	return 0;
 }
 
+/* return true if there is an overlap between any rdist */
+bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size)
+{
+	struct vgic_dist *d = &kvm->arch.vgic;
+	struct vgic_redist_region *rdreg;
+
+	list_for_each_entry(rdreg, &d->rd_regions, list) {
+		if ((base + size <= rdreg->base) ||
+			(rdreg->base + vgic_v3_rd_region_size(kvm, rdreg) <= base))
+			continue;
+		return true;
+	}
+	return false;
+}
+
 /*
  * Check for overlapping regions and for regions crossing the end of memory
  * for base addresses which have already been set.
@@ -455,6 +470,20 @@ struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rd_regions)
 	return NULL;
 }
 
+struct vgic_redist_region *vgic_v3_rdist_region_from_index(struct kvm *kvm,
+							   uint32_t index)
+{
+	struct list_head *rd_regions = &kvm->arch.vgic.rd_regions;
+	struct vgic_redist_region *rdreg;
+
+	list_for_each_entry(rdreg, rd_regions, list) {
+		if (rdreg->index == index)
+			return rdreg;
+	}
+	return NULL;
+}
+
+
 int vgic_v3_map_resources(struct kvm *kvm)
 {
 	int ret = 0;
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index d5e89b8..7feaad6 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -259,6 +259,20 @@ vgic_v3_redist_region_full(struct vgic_redist_region *region)
 
 struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rdregs);
 
+static inline size_t
+vgic_v3_rd_region_size(struct kvm *kvm, struct vgic_redist_region *rdreg)
+{
+	if (!rdreg->count)
+		return atomic_read(&kvm->online_vcpus) * KVM_VGIC_V3_REDIST_SIZE;
+	else
+		return rdreg->count * KVM_VGIC_V3_REDIST_SIZE;
+}
+
+struct vgic_redist_region *vgic_v3_rdist_region_from_index(struct kvm *kvm,
+							   uint32_t index);
+
+bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size);
+
 int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its,
 			 u32 devid, u32 eventid, struct vgic_irq **irq);
 struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi);
-- 
2.5.5

[RFC v2 07/12] KVM: arm/arm64: Adapt vgic_v3_check_base to multiple rdist regions

[Eric Auger]

We introduce a new helper to check there is no overlap between
dist region (if set) and registered rdist regions. This both
handles the case of legacy single rdist region (implicitly sized
with the number of online vcpus) and the new case of multiple
explicitly sized rdist regions.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 virt/kvm/arm/vgic/vgic-v3.c | 26 +++++++++-----------------
 1 file changed, 9 insertions(+), 17 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 9a19129..993939d 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -426,31 +426,23 @@ bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size)
 bool vgic_v3_check_base(struct kvm *kvm)
 {
 	struct vgic_dist *d = &kvm->arch.vgic;
-	gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;
-	struct vgic_redist_region *rdreg =
-		list_first_entry(&d->rd_regions,
-				 struct vgic_redist_region, list);
-
-	redist_size *= atomic_read(&kvm->online_vcpus);
+	struct vgic_redist_region *rdreg;
 
 	if (!IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) &&
 	    d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
 		return false;
 
-	if (rdreg && (rdreg->base + redist_size < rdreg->base))
-		return false;
+	list_for_each_entry(rdreg, &d->rd_regions, list) {
+		if (rdreg->base + vgic_v3_rd_region_size(kvm, rdreg) <
+			rdreg->base)
+			return false;
+	}
 
-	/* Both base addresses must be set to check if they overlap */
-	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) || !rdreg)
+	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base))
 		return true;
 
-	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= rdreg->base)
-		return true;
-
-	if (rdreg->base + redist_size <= d->vgic_dist_base)
-		return true;
-
-	return false;
+	return !vgic_v3_rdist_overlap(kvm, d->vgic_dist_base,
+				      KVM_VGIC_V3_DIST_SIZE);
 }
 
 /**
-- 
2.5.5

[RFC v2 08/12] KVM: arm/arm64: Check vcpu redist base before registering an iodev

[Eric Auger]

As we are going to register several redist regions,
vgic_register_all_redist_iodevs() may be called several times. We need
to register a redist_iodev for a given vcpu only once. So let's
check if the base address has already been set. Initialize this latter
in kvm_vgic_vcpu_early_init().

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 virt/kvm/arm/vgic/vgic-init.c    | 3 +++
 virt/kvm/arm/vgic/vgic-mmio-v3.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index ef509e6..78e0c2f 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -82,6 +82,9 @@ void kvm_vgic_vcpu_early_init(struct kvm_vcpu *vcpu)
 	INIT_LIST_HEAD(&vgic_cpu->ap_list_head);
 	spin_lock_init(&vgic_cpu->ap_list_lock);
 
+	vgic_cpu->rd_iodev.base_addr = VGIC_ADDR_UNDEF;
+	vgic_cpu->sgi_iodev.base_addr = VGIC_ADDR_UNDEF;
+
 	/*
 	 * Enable and configure all SGIs to be edge-triggered and
 	 * configure all PPIs as level-triggered.
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 2f3b9e5..89faadc 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -592,6 +592,9 @@ int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 	gpa_t rd_base, sgi_base;
 	int ret;
 
+	if (!IS_VGIC_ADDR_UNDEF(vgic_cpu->rd_iodev.base_addr))
+		return 0;
+
 	/*
 	 * We may be creating VCPUs before having set the base address for the
 	 * redistributor region, in which case we will come back to this
-- 
2.5.5

[RFC v2 09/12] KVM: arm/arm64: Check all vcpu redistributors are set on map_resources

[Eric Auger]

On vcpu first run, we eventually know the actual number of vcpus.
This is a synchronization point to check all redistributors regions
were assigned. On kvm_vgic_map_resources() we check both dist and
redist were set, eventually check potential base address inconsistencies.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 virt/kvm/arm/vgic/vgic-v3.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 993939d..855fc19 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -478,16 +478,25 @@ struct vgic_redist_region *vgic_v3_rdist_region_from_index(struct kvm *kvm,
 
 int vgic_v3_map_resources(struct kvm *kvm)
 {
-	int ret = 0;
 	struct vgic_dist *dist = &kvm->arch.vgic;
-	struct vgic_redist_region *rdreg =
-		list_first_entry(&dist->rd_regions,
-				 struct vgic_redist_region, list);
+	struct kvm_vcpu *vcpu;
+	int ret = 0;
+	int c;
 
 	if (vgic_ready(kvm))
 		goto out;
 
-	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base) || !rdreg) {
+	kvm_for_each_vcpu(c, vcpu, kvm) {
+		struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
+
+		if (IS_VGIC_ADDR_UNDEF(vgic_cpu->rd_iodev.base_addr)) {
+			kvm_err("vcpu %d redistributor base not set\n", c);
+			ret = -ENXIO;
+			goto out;
+		}
+	}
+
+	if (IS_VGIC_ADDR_UNDEF(dist->vgic_dist_base)) {
 		kvm_err("Need to set vgic distributor addresses first\n");
 		ret = -ENXIO;
 		goto out;
-- 
2.5.5

[RFC v2 10/12] KVM: arm/arm64: Add KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION

[Eric Auger]

This new attribute allows the userspace to set the base address
of a reditributor region, relaxing the constraint of having all
consecutive redistibutor frames contiguous.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 arch/arm/include/uapi/asm/kvm.h   | 7 ++++---
 arch/arm64/include/uapi/asm/kvm.h | 7 ++++---
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
index 6edd177..ce67f1d 100644
--- a/arch/arm/include/uapi/asm/kvm.h
+++ b/arch/arm/include/uapi/asm/kvm.h
@@ -88,9 +88,10 @@ struct kvm_regs {
 #define KVM_VGIC_V2_CPU_SIZE		0x2000
 
 /* Supported VGICv3 address types  */
-#define KVM_VGIC_V3_ADDR_TYPE_DIST	2
-#define KVM_VGIC_V3_ADDR_TYPE_REDIST	3
-#define KVM_VGIC_ITS_ADDR_TYPE		4
+#define KVM_VGIC_V3_ADDR_TYPE_DIST		2
+#define KVM_VGIC_V3_ADDR_TYPE_REDIST		3
+#define KVM_VGIC_ITS_ADDR_TYPE			4
+#define KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION	5
 
 #define KVM_VGIC_V3_DIST_SIZE		SZ_64K
 #define KVM_VGIC_V3_REDIST_SIZE		(2 * SZ_64K)
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index 9abbf30..ef8ad3b 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -88,9 +88,10 @@ struct kvm_regs {
 #define KVM_VGIC_V2_CPU_SIZE		0x2000
 
 /* Supported VGICv3 address types  */
-#define KVM_VGIC_V3_ADDR_TYPE_DIST	2
-#define KVM_VGIC_V3_ADDR_TYPE_REDIST	3
-#define KVM_VGIC_ITS_ADDR_TYPE		4
+#define KVM_VGIC_V3_ADDR_TYPE_DIST		2
+#define KVM_VGIC_V3_ADDR_TYPE_REDIST		3
+#define KVM_VGIC_ITS_ADDR_TYPE			4
+#define KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION	5
 
 #define KVM_VGIC_V3_DIST_SIZE		SZ_64K
 #define KVM_VGIC_V3_REDIST_SIZE		(2 * SZ_64K)
-- 
2.5.5

[RFC v2 11/12] KVM: arm/arm64: Implement KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION

[Eric Auger]

Now all the internals are ready to handle multiple redistributor
regions, let's allow the userspace to register them.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 virt/kvm/arm/vgic/vgic-kvm-device.c | 40 +++++++++++++++++++++++++++++++++++--
 virt/kvm/arm/vgic/vgic-mmio-v3.c    |  4 ++--
 virt/kvm/arm/vgic/vgic.h            |  9 ++++++++-
 3 files changed, 48 insertions(+), 5 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
index e7b5a86..a2b99e4 100644
--- a/virt/kvm/arm/vgic/vgic-kvm-device.c
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -65,7 +65,8 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
 {
 	int r = 0;
 	struct vgic_dist *vgic = &kvm->arch.vgic;
-	phys_addr_t *addr_ptr, alignment;
+	phys_addr_t *addr_ptr = NULL;
+	phys_addr_t alignment;
 	uint64_t undef_value = VGIC_ADDR_UNDEF;
 
 	mutex_lock(&kvm->lock);
@@ -92,7 +93,7 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
 		if (r)
 			break;
 		if (write) {
-			r = vgic_v3_set_redist_base(kvm, *addr);
+			r = vgic_v3_set_redist_base(kvm, 0, *addr, 0);
 			goto out;
 		}
 		rdreg = list_first_entry(&vgic->rd_regions,
@@ -103,6 +104,40 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
 			addr_ptr = &rdreg->base;
 		break;
 	}
+	case KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION:
+	{
+		struct vgic_redist_region *rdreg;
+		uint8_t index;
+
+		r = vgic_check_type(kvm, KVM_DEV_TYPE_ARM_VGIC_V3);
+		if (r)
+			break;
+
+		index = *addr & KVM_VGIC_V3_RDIST_INDEX_MASK;
+
+		if (write) {
+			gpa_t base = *addr & KVM_VGIC_V3_RDIST_BASE_MASK;
+			uint32_t count = (*addr & KVM_VGIC_V3_RDIST_COUNT_MASK)
+					>> KVM_VGIC_V3_RDIST_COUNT_SHIFT;
+			uint8_t flags = (*addr & KVM_VGIC_V3_RDIST_FLAGS_MASK)
+					>> KVM_VGIC_V3_RDIST_FLAGS_SHIFT;
+
+			if (!count || flags)
+				r = -EINVAL;
+			else
+				r = vgic_v3_set_redist_base(kvm, index,
+							    base, count);
+			goto out;
+		}
+
+		rdreg = vgic_v3_rdist_region_from_index(kvm, index);
+		if (!rdreg)
+			r = -ENODEV;
+
+		*addr_ptr = rdreg->base & index &
+			(uint64_t)rdreg->count << KVM_VGIC_V3_RDIST_COUNT_SHIFT;
+		break;
+	}
 	default:
 		r = -ENODEV;
 	}
@@ -674,6 +709,7 @@ static int vgic_v3_has_attr(struct kvm_device *dev,
 		switch (attr->attr) {
 		case KVM_VGIC_V3_ADDR_TYPE_DIST:
 		case KVM_VGIC_V3_ADDR_TYPE_REDIST:
+		case KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION:
 			return 0;
 		}
 		break;
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 89faadc..45287a0 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -766,11 +766,11 @@ static int vgic_v3_insert_redist_region(struct kvm *kvm, uint32_t index,
 	return ret;
 }
 
-int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
+int vgic_v3_set_redist_base(struct kvm *kvm, u32 index, u64 addr, u32 count)
 {
 	int ret;
 
-	ret = vgic_v3_insert_redist_region(kvm, 0, addr, 0);
+	ret = vgic_v3_insert_redist_region(kvm, index, addr, count);
 	if (ret)
 		return ret;
 
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 7feaad6..5c70bfd 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -96,6 +96,13 @@
 /* we only support 64 kB translation table page size */
 #define KVM_ITS_L1E_ADDR_MASK		GENMASK_ULL(51, 16)
 
+#define KVM_VGIC_V3_RDIST_INDEX_MASK	GENMASK_ULL(11, 0)
+#define KVM_VGIC_V3_RDIST_FLAGS_MASK	GENMASK_ULL(15, 12)
+#define KVM_VGIC_V3_RDIST_FLAGS_SHIFT	12
+#define KVM_VGIC_V3_RDIST_BASE_MASK	GENMASK_ULL(51, 16)
+#define KVM_VGIC_V3_RDIST_COUNT_MASK	GENMASK_ULL(63, 52)
+#define KVM_VGIC_V3_RDIST_COUNT_SHIFT	52
+
 /* Requires the irq_lock to be held by the caller. */
 static inline bool irq_is_pending(struct vgic_irq *irq)
 {
@@ -198,7 +205,7 @@ int vgic_v3_probe(const struct gic_kvm_info *info);
 int vgic_v3_map_resources(struct kvm *kvm);
 int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq);
 int vgic_v3_save_pending_tables(struct kvm *kvm);
-int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr);
+int vgic_v3_set_redist_base(struct kvm *kvm, u32 index, u64 addr, u32 count);
 int vgic_register_redist_iodev(struct kvm_vcpu *vcpu);
 bool vgic_v3_check_base(struct kvm *kvm);
 
-- 
2.5.5

[RFC v2 12/12] KVM: arm/arm64: Bump VGIC_V3_MAX_CPUS to 512

[Eric Auger]

Let's raise the number of supported vcpus along with
vgic v3 now that HW is looming with more physical CPUs.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 include/kvm/arm_vgic.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 64994d0..f36bdf1 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -28,7 +28,7 @@
 
 #include <linux/irqchip/arm-gic-v4.h>
 
-#define VGIC_V3_MAX_CPUS	255
+#define VGIC_V3_MAX_CPUS	512
 #define VGIC_V2_MAX_CPUS	8
 #define VGIC_NR_IRQS_LEGACY     256
 #define VGIC_NR_SGIS		16
-- 
2.5.5

Re: [RFC v2 01/12] KVM: arm/arm64: Set dist->spis to NULL after kfree

[Marc Zyngier]

On 27/03/18 15:04, Eric Auger wrote:
> in case kvm_vgic_map_resources() fails, typically if the vgic
> distributor is not defined, __kvm_vgic_destroy will be called
> several times. Indeed kvm_vgic_map_resources() is called on
> first vcpu run. As a result dist->spis is freeed more than once
> and on the second time it causes a "kernel BUG at mm/slub.c:3912!"
> 
> Set dist->spis to NULL to avoid the crash.
> 
> Signed-off-by: Eric Auger <eric.auger@redhat.com>

Fixes: ad275b8bb1e6 ("KVM: arm/arm64: vgic-new: vgic_init: implement
vgic_init")

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>

	M.
-- 
Jazz is not dead. It just smells funny...

Re: [RFC v2 01/12] KVM: arm/arm64: Set dist->spis to NULL after kfree

[Auger Eric]

Hi Marc,
On 27/03/18 19:10, Marc Zyngier wrote:
> On 27/03/18 15:04, Eric Auger wrote:
>> in case kvm_vgic_map_resources() fails, typically if the vgic
>> distributor is not defined, __kvm_vgic_destroy will be called
>> several times. Indeed kvm_vgic_map_resources() is called on
>> first vcpu run. As a result dist->spis is freeed more than once
>> and on the second time it causes a "kernel BUG at mm/slub.c:3912!"
>>
>> Set dist->spis to NULL to avoid the crash.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> 
> Fixes: ad275b8bb1e6 ("KVM: arm/arm64: vgic-new: vgic_init: implement
> vgic_init")
Sorry for the oversight :-(
> 
> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Thanks

Eric
> 
> 	M.
> 

Re: [RFC v2 11/12] KVM: arm/arm64: Implement KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION

[Peter Maydell]

On 27 March 2018 at 15:04, Eric Auger <eric.auger@redhat.com> wrote:
> Now all the internals are ready to handle multiple redistributor
> regions, let's allow the userspace to register them.
>
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> ---
>  virt/kvm/arm/vgic/vgic-kvm-device.c | 40 +++++++++++++++++++++++++++++++++++--
>  virt/kvm/arm/vgic/vgic-mmio-v3.c    |  4 ++--
>  virt/kvm/arm/vgic/vgic.h            |  9 ++++++++-
>  3 files changed, 48 insertions(+), 5 deletions(-)
>
> diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
> index e7b5a86..a2b99e4 100644
> --- a/virt/kvm/arm/vgic/vgic-kvm-device.c
> +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
> @@ -65,7 +65,8 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
>  {
>         int r = 0;
>         struct vgic_dist *vgic = &kvm->arch.vgic;
> -       phys_addr_t *addr_ptr, alignment;
> +       phys_addr_t *addr_ptr = NULL;
> +       phys_addr_t alignment;
>         uint64_t undef_value = VGIC_ADDR_UNDEF;
>
>         mutex_lock(&kvm->lock);
> @@ -92,7 +93,7 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
>                 if (r)
>                         break;
>                 if (write) {
> -                       r = vgic_v3_set_redist_base(kvm, *addr);
> +                       r = vgic_v3_set_redist_base(kvm, 0, *addr, 0);
>                         goto out;
>                 }
>                 rdreg = list_first_entry(&vgic->rd_regions,
> @@ -103,6 +104,40 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
>                         addr_ptr = &rdreg->base;
>                 break;
>         }
> +       case KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION:
> +       {
> +               struct vgic_redist_region *rdreg;
> +               uint8_t index;
> +
> +               r = vgic_check_type(kvm, KVM_DEV_TYPE_ARM_VGIC_V3);
> +               if (r)
> +                       break;
> +
> +               index = *addr & KVM_VGIC_V3_RDIST_INDEX_MASK;
> +
> +               if (write) {
> +                       gpa_t base = *addr & KVM_VGIC_V3_RDIST_BASE_MASK;
> +                       uint32_t count = (*addr & KVM_VGIC_V3_RDIST_COUNT_MASK)
> +                                       >> KVM_VGIC_V3_RDIST_COUNT_SHIFT;
> +                       uint8_t flags = (*addr & KVM_VGIC_V3_RDIST_FLAGS_MASK)
> +                                       >> KVM_VGIC_V3_RDIST_FLAGS_SHIFT;
> +
> +                       if (!count || flags)
> +                               r = -EINVAL;
> +                       else
> +                               r = vgic_v3_set_redist_base(kvm, index,
> +                                                           base, count);
> +                       goto out;
> +               }
> +
> +               rdreg = vgic_v3_rdist_region_from_index(kvm, index);
> +               if (!rdreg)
> +                       r = -ENODEV;

Here you check whether rdreg is NULL...

> +
> +               *addr_ptr = rdreg->base & index &

...but here you dereference it anyway. Missing "goto out"/break/other
control flow?

> +                       (uint64_t)rdreg->count << KVM_VGIC_V3_RDIST_COUNT_SHIFT;
> +               break;
> +       }

I was looking for the code which checked "EINVAL if you
already used KVM_VGIC_V3_ADDR_TYPE_REDIST", but couldn't
see it. Is that handled by one of the helper functions?

>         default:
>                 r = -ENODEV;
>         }
> @@ -674,6 +709,7 @@ static int vgic_v3_has_attr(struct kvm_device *dev,
>                 switch (attr->attr) {
>                 case KVM_VGIC_V3_ADDR_TYPE_DIST:
>                 case KVM_VGIC_V3_ADDR_TYPE_REDIST:
> +               case KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION:
>                         return 0;
>                 }
>                 break;
> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
> index 89faadc..45287a0 100644
> --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
> +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
> @@ -766,11 +766,11 @@ static int vgic_v3_insert_redist_region(struct kvm *kvm, uint32_t index,
>         return ret;
>  }
>
> -int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
> +int vgic_v3_set_redist_base(struct kvm *kvm, u32 index, u64 addr, u32 count)
>  {
>         int ret;
>
> -       ret = vgic_v3_insert_redist_region(kvm, 0, addr, 0);
> +       ret = vgic_v3_insert_redist_region(kvm, index, addr, count);
>         if (ret)
>                 return ret;

thanks
-- PMM

Re: [RFC v2 11/12] KVM: arm/arm64: Implement KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION

[Auger Eric]

Hi Peter,

On 28/03/18 20:55, Peter Maydell wrote:
> On 27 March 2018 at 15:04, Eric Auger <eric.auger@redhat.com> wrote:
>> Now all the internals are ready to handle multiple redistributor
>> regions, let's allow the userspace to register them.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>> ---
>>  virt/kvm/arm/vgic/vgic-kvm-device.c | 40 +++++++++++++++++++++++++++++++++++--
>>  virt/kvm/arm/vgic/vgic-mmio-v3.c    |  4 ++--
>>  virt/kvm/arm/vgic/vgic.h            |  9 ++++++++-
>>  3 files changed, 48 insertions(+), 5 deletions(-)
>>
>> diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
>> index e7b5a86..a2b99e4 100644
>> --- a/virt/kvm/arm/vgic/vgic-kvm-device.c
>> +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
>> @@ -65,7 +65,8 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
>>  {
>>         int r = 0;
>>         struct vgic_dist *vgic = &kvm->arch.vgic;
>> -       phys_addr_t *addr_ptr, alignment;
>> +       phys_addr_t *addr_ptr = NULL;
>> +       phys_addr_t alignment;
>>         uint64_t undef_value = VGIC_ADDR_UNDEF;
>>
>>         mutex_lock(&kvm->lock);
>> @@ -92,7 +93,7 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
>>                 if (r)
>>                         break;
>>                 if (write) {
>> -                       r = vgic_v3_set_redist_base(kvm, *addr);
>> +                       r = vgic_v3_set_redist_base(kvm, 0, *addr, 0);
>>                         goto out;
>>                 }
>>                 rdreg = list_first_entry(&vgic->rd_regions,
>> @@ -103,6 +104,40 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
>>                         addr_ptr = &rdreg->base;
>>                 break;
>>         }
>> +       case KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION:
>> +       {
>> +               struct vgic_redist_region *rdreg;
>> +               uint8_t index;
>> +
>> +               r = vgic_check_type(kvm, KVM_DEV_TYPE_ARM_VGIC_V3);
>> +               if (r)
>> +                       break;
>> +
>> +               index = *addr & KVM_VGIC_V3_RDIST_INDEX_MASK;
>> +
>> +               if (write) {
>> +                       gpa_t base = *addr & KVM_VGIC_V3_RDIST_BASE_MASK;
>> +                       uint32_t count = (*addr & KVM_VGIC_V3_RDIST_COUNT_MASK)
>> +                                       >> KVM_VGIC_V3_RDIST_COUNT_SHIFT;
>> +                       uint8_t flags = (*addr & KVM_VGIC_V3_RDIST_FLAGS_MASK)
>> +                                       >> KVM_VGIC_V3_RDIST_FLAGS_SHIFT;
>> +
>> +                       if (!count || flags)
>> +                               r = -EINVAL;
>> +                       else
>> +                               r = vgic_v3_set_redist_base(kvm, index,
>> +                                                           base, count);
>> +                       goto out;
>> +               }
>> +
>> +               rdreg = vgic_v3_rdist_region_from_index(kvm, index);
>> +               if (!rdreg)
>> +                       r = -ENODEV;
> 
> Here you check whether rdreg is NULL...
> 
>> +
>> +               *addr_ptr = rdreg->base & index &
> 
> ...but here you dereference it anyway. Missing "goto out"/break/other
> control flow?
definitively, goto default.
> 
>> +                       (uint64_t)rdreg->count << KVM_VGIC_V3_RDIST_COUNT_SHIFT;
>> +               break;
>> +       }
> 
> I was looking for the code which checked "EINVAL if you
> already used KVM_VGIC_V3_ADDR_TYPE_REDIST", but couldn't
> see it. Is that handled by one of the helper functions?

No you're right. At the moment I only check the legacy API is not called
after a first redist region has been registered (with legacy or new
API). I will add this check in next version in
vgic_v3_insert_redist_region().

Also something I forgot to document is the userspace must register the
REDIST_REGIONS (so using the new API) starting with index 0 and
continuously incrementing the index by 1.

Thanks

Eric
> 
>>         default:
>>                 r = -ENODEV;
>>         }
>> @@ -674,6 +709,7 @@ static int vgic_v3_has_attr(struct kvm_device *dev,
>>                 switch (attr->attr) {
>>                 case KVM_VGIC_V3_ADDR_TYPE_DIST:
>>                 case KVM_VGIC_V3_ADDR_TYPE_REDIST:
>> +               case KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION:
>>                         return 0;
>>                 }
>>                 break;
>> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> index 89faadc..45287a0 100644
>> --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
>> @@ -766,11 +766,11 @@ static int vgic_v3_insert_redist_region(struct kvm *kvm, uint32_t index,
>>         return ret;
>>  }
>>
>> -int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
>> +int vgic_v3_set_redist_base(struct kvm *kvm, u32 index, u64 addr, u32 count)
>>  {
>>         int ret;
>>
>> -       ret = vgic_v3_insert_redist_region(kvm, 0, addr, 0);
>> +       ret = vgic_v3_insert_redist_region(kvm, index, addr, count);
>>         if (ret)
>>                 return ret;
> 
> thanks
> -- PMM
> 

Re: [RFC v2 02/12] KVM: arm/arm64: Document KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION

[Christoffer Dall]

Hi Eric,

On Tue, Mar 27, 2018 at 04:04:06PM +0200, Eric Auger wrote:
> We introduce a new KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attribute in
> KVM_DEV_ARM_VGIC_GRP_ADDR group. It allows userspace to provide the
> base address and size of a redistributor region
> 
> Compared to KVM_VGIC_V3_ADDR_TYPE_REDIST, this new attribute allows
> to declare several separate redistributor regions.
> 
> So the whole redist space does not need to be contiguous anymore.
> 
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> ---
>  Documentation/virtual/kvm/devices/arm-vgic-v3.txt | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
> index 9293b45..0ded904 100644
> --- a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
> +++ b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
> @@ -27,6 +27,24 @@ Groups:
>        VCPU and all of the redistributor pages are contiguous.
>        Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
>        This address needs to be 64K aligned.
> +
> +    KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION (rw, 64-bit)
> +      The attr field of kvm_device_attr encodes 3 values:
> +      bits:     | 63   ....  52  |  51   ....   16 | 15 - 12  |11 - 0
> +      values:   |     count      |       base      |  flags   | index
> +      - index encodes the unique redistributor region index
> +      - flags: reserved for future use, currently 0
> +      - base field encodes bits [51:16] of the guest physical base address
> +        of the first redistributor in the region. There are two 64K pages
> +        for each VCPU and all of the redistributor pages are contiguous

should this be two 64K pages for the number of redistributors in this
region as specified by count ?

> +        within the redistributor region.
> +      - count encodes the number of redistributors in the region.

I assume it's implied that the user must register a total number of
redistributors across all the regions that matches the number of vcpus,
and that otherwise something bad happens?

> +      Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
> +
> +  It is invalid to mix calls with KVM_VGIC_V3_ADDR_TYPE_REDIST and
> +  KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attributes. When attempted an
> +  -EINVAL error is returned.
> +
>    Errors:
>      -E2BIG:  Address outside of addressable IPA range
>      -EINVAL: Incorrectly aligned address
> -- 
> 2.5.5
> 

Thanks,
-Christoffer

Re: [RFC v2 02/12] KVM: arm/arm64: Document KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION

[Auger Eric]

Hi Christoffer,

> Hi Eric,
> 
> On Tue, Mar 27, 2018 at 04:04:06PM +0200, Eric Auger wrote:
>> We introduce a new KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attribute in
>> KVM_DEV_ARM_VGIC_GRP_ADDR group. It allows userspace to provide the
>> base address and size of a redistributor region
>>
>> Compared to KVM_VGIC_V3_ADDR_TYPE_REDIST, this new attribute allows
>> to declare several separate redistributor regions.
>>
>> So the whole redist space does not need to be contiguous anymore.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>> ---
>>  Documentation/virtual/kvm/devices/arm-vgic-v3.txt | 18 ++++++++++++++++++
>>  1 file changed, 18 insertions(+)
>>
>> diff --git a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
>> index 9293b45..0ded904 100644
>> --- a/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
>> +++ b/Documentation/virtual/kvm/devices/arm-vgic-v3.txt
>> @@ -27,6 +27,24 @@ Groups:
>>        VCPU and all of the redistributor pages are contiguous.
>>        Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
>>        This address needs to be 64K aligned.
>> +
>> +    KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION (rw, 64-bit)
>> +      The attr field of kvm_device_attr encodes 3 values:
>> +      bits:     | 63   ....  52  |  51   ....   16 | 15 - 12  |11 - 0
>> +      values:   |     count      |       base      |  flags   | index
>> +      - index encodes the unique redistributor region index
>> +      - flags: reserved for future use, currently 0
>> +      - base field encodes bits [51:16] of the guest physical base address
>> +        of the first redistributor in the region. There are two 64K pages
>> +        for each VCPU and all of the redistributor pages are contiguous
> 
> should this be two 64K pages for the number of redistributors in this
> region as specified by count ?
yes it is, I will reword.
> 
>> +        within the redistributor region.
>> +      - count encodes the number of redistributors in the region.
> 
> I assume it's implied that the user must register a total number of
> redistributors across all the regions that matches the number of vcpus,
> and that otherwise something bad happens?

Yes the regions registered by the userspace must be large enough to
assign all the vcpu redistributors. Otherwise an error is produced on
first vcpu run (on map_resources). At that time the number of vcpu is
frozen and we can perform the check.

Thanks

Eric
> 
>> +      Only valid for KVM_DEV_TYPE_ARM_VGIC_V3.
>> +
>> +  It is invalid to mix calls with KVM_VGIC_V3_ADDR_TYPE_REDIST and
>> +  KVM_VGIC_V3_ADDR_TYPE_REDIST_REGION attributes. When attempted an
>> +  -EINVAL error is returned.
>> +
>>    Errors:
>>      -E2BIG:  Address outside of addressable IPA range
>>      -EINVAL: Incorrectly aligned address
>> -- 
>> 2.5.5
>>
> 
> Thanks,
> -Christoffer
>