[PULL 00/27] KVM/ARM GICv4 Support for v4.15

[PULL 00/27] KVM/ARM GICv4 Support for v4.15

[Christoffer Dall]

Hi Paolo and Radim,

Here is the second pull request for KVM/ARM for v4.15. These changes
introduce GICv4 support in KVM/ARM, allowing direct injection of LPIs
from devices generating MSIs into VMs.  The changes rely on irqchip
infrastructure for GICv4 already merged in tip:irq/core.

The pull request is based on kvm-arm-for-v4.15 plus 722c908f84c6 merged
from tip:irq/core.  The diffstat has been trimmed to only show the
changes between the merge base mentioned above and the KVM/ARM side of
GICv4 support, and does not include the additional changes in KVM not
present in tip:irq/core.

I expect that pulling this into the KVM tree after the irq/core changes
land in Linus' tree should result in a clean subsequent pull request
upstream, but let me know if you want me to work this out in some other
way.

The following changes since commit 722c908f84c67bf120105ca870675cadc1bb7b20:

  Merge tag 'irqchip-4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core (2017-11-02 19:18:08 +0100)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvm-arm-gicv4-for-v4.15

for you to fetch changes up to 95b110ab9a093b5baf3a72e51f71279368d618e2:

  KVM: arm/arm64: Don't queue VLPIs on INV/INVALL (2017-11-10 09:59:20 +0100)

Thanks,
-Christoffer

Christoffer Dall (2):
  KVM: arm/arm64: Fix GICv4 ITS initialization issues
  KVM: arm/arm64: Don't queue VLPIs on INV/INVALL

Eric Auger (2):
  KVM: arm/arm64: register irq bypass consumer on ARM/ARM64
  KVM: arm/arm64: vgic: restructure kvm_vgic_(un)map_phys_irq

Marc Zyngier (23):
  KVM: arm: Select ARM_GIC_V3 and ARM_GIC_V3_ITS
  KVM: arm/arm64: vgic: Move kvm_vgic_destroy call around
  KVM: arm/arm64: vITS: Add MSI translation helpers
  KVM: arm/arm64: vITS: Add a helper to update the affinity of an LPI
  KVM: arm/arm64: GICv4: Add property field and per-VM predicate
  KVM: arm/arm64: GICv4: Add init/teardown of the per-VM vPE irq domain
  KVM: arm/arm64: GICv4: Wire mapping/unmapping of VLPIs in VFIO irq
    bypass
  KVM: arm/arm64: GICv4: Handle INT command applied to a VLPI
  KVM: arm/arm64: GICv4: Unmap VLPI when freeing an LPI
  KVM: arm/arm64: GICv4: Propagate affinity changes to the physical ITS
  KVM: arm/arm64: GICv4: Handle CLEAR applied to a VLPI
  KVM: arm/arm64: GICv4: Handle MOVALL applied to a vPE
  KVM: arm/arm64: GICv4: Propagate property updates to VLPIs
  KVM: arm/arm64: GICv4: Handle INVALL applied to a vPE
  KVM: arm/arm64: GICv4: Use pending_last as a scheduling hint
  KVM: arm/arm64: GICv4: Add doorbell interrupt handling
  KVM: arm/arm64: GICv4: Use the doorbell interrupt as an unblocking
    source
  KVM: arm/arm64: GICv4: Hook vPE scheduling into vgic flush/sync
  KVM: arm/arm64: GICv4: Enable virtual cpuif if VLPIs can be delivered
  KVM: arm/arm64: GICv4: Prevent a VM using GICv4 from being saved
  KVM: arm/arm64: GICv4: Prevent userspace from changing doorbell
    affinity
  KVM: arm/arm64: GICv4: Enable VLPI support
  KVM: arm/arm64: GICv4: Theory of operations

 Documentation/admin-guide/kernel-parameters.txt    |   4 +
 Documentation/virtual/kvm/devices/arm-vgic-its.txt |   2 +
 arch/arm/kvm/Kconfig                               |   5 +
 arch/arm/kvm/Makefile                              |   1 +
 arch/arm64/kvm/Kconfig                             |   3 +
 arch/arm64/kvm/Makefile                            |   1 +
 include/kvm/arm_vgic.h                             |  41 ++-
 virt/kvm/arm/arch_timer.c                          |  24 +-
 virt/kvm/arm/arm.c                                 |  48 ++-
 virt/kvm/arm/hyp/vgic-v3-sr.c                      |   9 +-
 virt/kvm/arm/vgic/vgic-init.c                      |   7 +
 virt/kvm/arm/vgic/vgic-its.c                       | 204 ++++++++----
 virt/kvm/arm/vgic/vgic-mmio-v3.c                   |   5 +
 virt/kvm/arm/vgic/vgic-v3.c                        |  14 +
 virt/kvm/arm/vgic/vgic-v4.c                        | 364 +++++++++++++++++++++
 virt/kvm/arm/vgic/vgic.c                           |  67 +++-
 virt/kvm/arm/vgic/vgic.h                           |  10 +
 17 files changed, 695 insertions(+), 114 deletions(-)
 create mode 100644 virt/kvm/arm/vgic/vgic-v4.c

-- 
2.14.2

[PULL 01/27] KVM: arm/arm64: register irq bypass consumer on ARM/ARM64

[Christoffer Dall]

From: Eric Auger <eric.auger@redhat.com>

This patch selects IRQ_BYPASS_MANAGER and HAVE_KVM_IRQ_BYPASS
configs for ARM/ARM64.

kvm_arch_has_irq_bypass() now is implemented and returns true.
As a consequence the irq bypass consumer will be registered for
ARM/ARM64 with the forwarding callbacks:

- stop/start: halt/resume guest execution
- add/del_producer: set/unset forwarding at vgic/irqchip level

We don't have any actual support yet, so nothing gets actually
forwarded.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
[maz: dropped the DEOI stuff for the time being in order to
      reduce the dependency chain, amended commit message]
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm/kvm/Kconfig   |  3 +++
 arch/arm64/kvm/Kconfig |  3 +++
 virt/kvm/arm/arm.c     | 40 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 46 insertions(+)

diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
index 90d0176fb30d..4e2b192a030a 100644
--- a/arch/arm/kvm/Kconfig
+++ b/arch/arm/kvm/Kconfig
@@ -3,6 +3,7 @@
 #
 
 source "virt/kvm/Kconfig"
+source "virt/lib/Kconfig"
 
 menuconfig VIRTUALIZATION
 	bool "Virtualization"
@@ -35,6 +36,8 @@ config KVM
 	select HAVE_KVM_IRQCHIP
 	select HAVE_KVM_IRQ_ROUTING
 	select HAVE_KVM_MSI
+	select IRQ_BYPASS_MANAGER
+	select HAVE_KVM_IRQ_BYPASS
 	depends on ARM_VIRT_EXT && ARM_LPAE && ARM_ARCH_TIMER
 	---help---
 	  Support hosting virtualized guest machines.
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index 52cb7ad9b2fd..7e0d6e63cc71 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -3,6 +3,7 @@
 #
 
 source "virt/kvm/Kconfig"
+source "virt/lib/Kconfig"
 
 menuconfig VIRTUALIZATION
 	bool "Virtualization"
@@ -35,6 +36,8 @@ config KVM
 	select HAVE_KVM_MSI
 	select HAVE_KVM_IRQCHIP
 	select HAVE_KVM_IRQ_ROUTING
+	select IRQ_BYPASS_MANAGER
+	select HAVE_KVM_IRQ_BYPASS
 	---help---
 	  Support hosting virtualized guest machines.
 	  We don't support KVM with 16K page tables yet, due to the multiple
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index bc126fb99a3d..79f8ddd604c1 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -27,6 +27,8 @@
 #include <linux/mman.h>
 #include <linux/sched.h>
 #include <linux/kvm.h>
+#include <linux/kvm_irqfd.h>
+#include <linux/irqbypass.h>
 #include <trace/events/kvm.h>
 #include <kvm/arm_pmu.h>
 
@@ -1458,6 +1460,44 @@ struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr)
 	return NULL;
 }
 
+bool kvm_arch_has_irq_bypass(void)
+{
+	return true;
+}
+
+int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
+				      struct irq_bypass_producer *prod)
+{
+	struct kvm_kernel_irqfd *irqfd =
+		container_of(cons, struct kvm_kernel_irqfd, consumer);
+
+	return 0;
+}
+void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
+				      struct irq_bypass_producer *prod)
+{
+	struct kvm_kernel_irqfd *irqfd =
+		container_of(cons, struct kvm_kernel_irqfd, consumer);
+
+	return;
+}
+
+void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
+{
+	struct kvm_kernel_irqfd *irqfd =
+		container_of(cons, struct kvm_kernel_irqfd, consumer);
+
+	kvm_arm_halt_guest(irqfd->kvm);
+}
+
+void kvm_arch_irq_bypass_start(struct irq_bypass_consumer *cons)
+{
+	struct kvm_kernel_irqfd *irqfd =
+		container_of(cons, struct kvm_kernel_irqfd, consumer);
+
+	kvm_arm_resume_guest(irqfd->kvm);
+}
+
 /**
  * Initialize Hyp-mode and memory mappings on all CPUs.
  */
-- 
2.14.2

[PULL 02/27] KVM: arm/arm64: vgic: restructure kvm_vgic_(un)map_phys_irq

[Christoffer Dall]

From: Eric Auger <eric.auger@redhat.com>

We want to reuse the core of the map/unmap functions for IRQ
forwarding. Let's move the computation of the hwirq in
kvm_vgic_map_phys_irq and pass the linux IRQ as parameter.
the host_irq is added to struct vgic_irq.

We introduce kvm_vgic_map/unmap_irq which take a struct vgic_irq
handle as a parameter.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 include/kvm/arm_vgic.h    |  8 ++++---
 virt/kvm/arm/arch_timer.c | 24 +------------------
 virt/kvm/arm/vgic/vgic.c  | 60 +++++++++++++++++++++++++++++++++++------------
 3 files changed, 51 insertions(+), 41 deletions(-)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 34dba516ef24..53f631bdec75 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -116,6 +116,7 @@ struct vgic_irq {
 	bool hw;			/* Tied to HW IRQ */
 	struct kref refcount;		/* Used for LPIs */
 	u32 hwintid;			/* HW INTID number */
+	unsigned int host_irq;		/* linux irq corresponding to hwintid */
 	union {
 		u8 targets;			/* GICv2 target VCPUs mask */
 		u32 mpidr;			/* GICv3 target VCPU */
@@ -307,9 +308,10 @@ void kvm_vgic_init_cpu_hardware(void);
 
 int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid,
 			bool level, void *owner);
-int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, u32 virt_irq, u32 phys_irq);
-int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int virt_irq);
-bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, unsigned int virt_irq);
+int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq,
+			  u32 vintid);
+int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int vintid);
+bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, unsigned int vintid);
 
 int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu);
 
diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
index 4db54ff08d9e..4151250ce8da 100644
--- a/virt/kvm/arm/arch_timer.c
+++ b/virt/kvm/arm/arch_timer.c
@@ -817,9 +817,6 @@ int kvm_timer_enable(struct kvm_vcpu *vcpu)
 {
 	struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
 	struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
-	struct irq_desc *desc;
-	struct irq_data *data;
-	int phys_irq;
 	int ret;
 
 	if (timer->enabled)
@@ -837,26 +834,7 @@ int kvm_timer_enable(struct kvm_vcpu *vcpu)
 		return -EINVAL;
 	}
 
-	/*
-	 * Find the physical IRQ number corresponding to the host_vtimer_irq
-	 */
-	desc = irq_to_desc(host_vtimer_irq);
-	if (!desc) {
-		kvm_err("%s: no interrupt descriptor\n", __func__);
-		return -EINVAL;
-	}
-
-	data = irq_desc_get_irq_data(desc);
-	while (data->parent_data)
-		data = data->parent_data;
-
-	phys_irq = data->hwirq;
-
-	/*
-	 * Tell the VGIC that the virtual interrupt is tied to a
-	 * physical interrupt. We do that once per VCPU.
-	 */
-	ret = kvm_vgic_map_phys_irq(vcpu, vtimer->irq.irq, phys_irq);
+	ret = kvm_vgic_map_phys_irq(vcpu, host_vtimer_irq, vtimer->irq.irq);
 	if (ret)
 		return ret;
 
diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
index e54ef2fdf73d..a05a5700910b 100644
--- a/virt/kvm/arm/vgic/vgic.c
+++ b/virt/kvm/arm/vgic/vgic.c
@@ -17,6 +17,8 @@
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
 #include <linux/list_sort.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
 
 #include "vgic.h"
 
@@ -409,25 +411,56 @@ int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid,
 	return 0;
 }
 
-int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, u32 virt_irq, u32 phys_irq)
+/* @irq->irq_lock must be held */
+static int kvm_vgic_map_irq(struct kvm_vcpu *vcpu, struct vgic_irq *irq,
+			    unsigned int host_irq)
 {
-	struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, virt_irq);
+	struct irq_desc *desc;
+	struct irq_data *data;
+
+	/*
+	 * Find the physical IRQ number corresponding to @host_irq
+	 */
+	desc = irq_to_desc(host_irq);
+	if (!desc) {
+		kvm_err("%s: no interrupt descriptor\n", __func__);
+		return -EINVAL;
+	}
+	data = irq_desc_get_irq_data(desc);
+	while (data->parent_data)
+		data = data->parent_data;
+
+	irq->hw = true;
+	irq->host_irq = host_irq;
+	irq->hwintid = data->hwirq;
+	return 0;
+}
+
+/* @irq->irq_lock must be held */
+static inline void kvm_vgic_unmap_irq(struct vgic_irq *irq)
+{
+	irq->hw = false;
+	irq->hwintid = 0;
+}
+
+int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq,
+			  u32 vintid)
+{
+	struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, vintid);
 	unsigned long flags;
+	int ret;
 
 	BUG_ON(!irq);
 
 	spin_lock_irqsave(&irq->irq_lock, flags);
-
-	irq->hw = true;
-	irq->hwintid = phys_irq;
-
+	ret = kvm_vgic_map_irq(vcpu, irq, host_irq);
 	spin_unlock_irqrestore(&irq->irq_lock, flags);
 	vgic_put_irq(vcpu->kvm, irq);
 
-	return 0;
+	return ret;
 }
 
-int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int virt_irq)
+int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int vintid)
 {
 	struct vgic_irq *irq;
 	unsigned long flags;
@@ -435,14 +468,11 @@ int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int virt_irq)
 	if (!vgic_initialized(vcpu->kvm))
 		return -EAGAIN;
 
-	irq = vgic_get_irq(vcpu->kvm, vcpu, virt_irq);
+	irq = vgic_get_irq(vcpu->kvm, vcpu, vintid);
 	BUG_ON(!irq);
 
 	spin_lock_irqsave(&irq->irq_lock, flags);
-
-	irq->hw = false;
-	irq->hwintid = 0;
-
+	kvm_vgic_unmap_irq(irq);
 	spin_unlock_irqrestore(&irq->irq_lock, flags);
 	vgic_put_irq(vcpu->kvm, irq);
 
@@ -784,9 +814,9 @@ void vgic_kick_vcpus(struct kvm *kvm)
 	}
 }
 
-bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, unsigned int virt_irq)
+bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, unsigned int vintid)
 {
-	struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, virt_irq);
+	struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, vintid);
 	bool map_is_active;
 	unsigned long flags;
 
-- 
2.14.2

[PULL 03/27] KVM: arm: Select ARM_GIC_V3 and ARM_GIC_V3_ITS

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

The GICv4 support introduces a hard dependency between the KVM
core and the ITS infrastructure. arm64 already selects it at
the architecture level, but 32bit doesn't. In order to avoid
littering the kernel with #ifdefs, let's just select the whole
of the GICv3 suport code.

You know you want it.

Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm/kvm/Kconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/kvm/Kconfig b/arch/arm/kvm/Kconfig
index 4e2b192a030a..52b50af04e3b 100644
--- a/arch/arm/kvm/Kconfig
+++ b/arch/arm/kvm/Kconfig
@@ -23,6 +23,8 @@ config KVM
 	select PREEMPT_NOTIFIERS
 	select ANON_INODES
 	select ARM_GIC
+	select ARM_GIC_V3
+	select ARM_GIC_V3_ITS
 	select HAVE_KVM_CPU_RELAX_INTERCEPT
 	select HAVE_KVM_ARCH_TLB_FLUSH_ALL
 	select KVM_MMIO
-- 
2.14.2

[PULL 04/27] KVM: arm/arm64: vgic: Move kvm_vgic_destroy call around

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

The way we call kvm_vgic_destroy is a bit bizarre. We call it
*after* having freed the vcpus, which sort of defeats the point
of cleaning up things before that point.

Let's move kvm_vgic_destroy towards the beginning of kvm_arch_destroy_vm,
which seems more sensible.

Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/arm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 79f8ddd604c1..e1e947fe9bc2 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -177,6 +177,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
 {
 	int i;
 
+	kvm_vgic_destroy(kvm);
+
 	free_percpu(kvm->arch.last_vcpu_ran);
 	kvm->arch.last_vcpu_ran = NULL;
 
@@ -186,8 +188,6 @@ void kvm_arch_destroy_vm(struct kvm *kvm)
 			kvm->vcpus[i] = NULL;
 		}
 	}
-
-	kvm_vgic_destroy(kvm);
 }
 
 int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
-- 
2.14.2

[PULL 05/27] KVM: arm/arm64: vITS: Add MSI translation helpers

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

The whole MSI injection process is fairly monolithic. An MSI write
gets turned into an injected LPI in one swift go. But this is actually
a more fine-grained process:

- First, a virtual ITS gets selected using the doorbell address
- Then the DevID/EventID pair gets translated into an LPI
- Finally the LPI is injected

Since the GICv4 code needs the first two steps in order to match
an IRQ routing entry to an LPI, let's expose them as helpers,
and refactor the existing code to use them

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 95 +++++++++++++++++++++++++-------------------
 virt/kvm/arm/vgic/vgic.h     |  4 ++
 2 files changed, 58 insertions(+), 41 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 40791c121710..1de4e68ef1b6 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -505,19 +505,11 @@ static unsigned long vgic_mmio_read_its_idregs(struct kvm *kvm,
 	return 0;
 }
 
-/*
- * Find the target VCPU and the LPI number for a given devid/eventid pair
- * and make this IRQ pending, possibly injecting it.
- * Must be called with the its_lock mutex held.
- * Returns 0 on success, a positive error value for any ITS mapping
- * related errors and negative error values for generic errors.
- */
-static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its,
-				u32 devid, u32 eventid)
+int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its,
+			 u32 devid, u32 eventid, struct vgic_irq **irq)
 {
 	struct kvm_vcpu *vcpu;
 	struct its_ite *ite;
-	unsigned long flags;
 
 	if (!its->enabled)
 		return -EBUSY;
@@ -533,26 +525,61 @@ static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its,
 	if (!vcpu->arch.vgic_cpu.lpis_enabled)
 		return -EBUSY;
 
-	spin_lock_irqsave(&ite->irq->irq_lock, flags);
-	ite->irq->pending_latch = true;
-	vgic_queue_irq_unlock(kvm, ite->irq, flags);
-
+	*irq = ite->irq;
 	return 0;
 }
 
-static struct vgic_io_device *vgic_get_its_iodev(struct kvm_io_device *dev)
+struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi)
 {
+	u64 address;
+	struct kvm_io_device *kvm_io_dev;
 	struct vgic_io_device *iodev;
 
-	if (dev->ops != &kvm_io_gic_ops)
-		return NULL;
+	if (!vgic_has_its(kvm))
+		return ERR_PTR(-ENODEV);
 
-	iodev = container_of(dev, struct vgic_io_device, dev);
+	if (!(msi->flags & KVM_MSI_VALID_DEVID))
+		return ERR_PTR(-EINVAL);
+
+	address = (u64)msi->address_hi << 32 | msi->address_lo;
+
+	kvm_io_dev = kvm_io_bus_get_dev(kvm, KVM_MMIO_BUS, address);
+	if (!kvm_io_dev)
+		return ERR_PTR(-EINVAL);
 
+	if (kvm_io_dev->ops != &kvm_io_gic_ops)
+		return ERR_PTR(-EINVAL);
+
+	iodev = container_of(kvm_io_dev, struct vgic_io_device, dev);
 	if (iodev->iodev_type != IODEV_ITS)
-		return NULL;
+		return ERR_PTR(-EINVAL);
+
+	return iodev->its;
+}
+
+/*
+ * Find the target VCPU and the LPI number for a given devid/eventid pair
+ * and make this IRQ pending, possibly injecting it.
+ * Must be called with the its_lock mutex held.
+ * Returns 0 on success, a positive error value for any ITS mapping
+ * related errors and negative error values for generic errors.
+ */
+static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its,
+				u32 devid, u32 eventid)
+{
+	struct vgic_irq *irq = NULL;
+	unsigned long flags;
+	int err;
+
+	err = vgic_its_resolve_lpi(kvm, its, devid, eventid, &irq);
+	if (err)
+		return err;
 
-	return iodev;
+	spin_lock_irqsave(&irq->irq_lock, flags);
+	irq->pending_latch = true;
+	vgic_queue_irq_unlock(kvm, irq, flags);
+
+	return 0;
 }
 
 /*
@@ -563,30 +590,16 @@ static struct vgic_io_device *vgic_get_its_iodev(struct kvm_io_device *dev)
  */
 int vgic_its_inject_msi(struct kvm *kvm, struct kvm_msi *msi)
 {
-	u64 address;
-	struct kvm_io_device *kvm_io_dev;
-	struct vgic_io_device *iodev;
+	struct vgic_its *its;
 	int ret;
 
-	if (!vgic_has_its(kvm))
-		return -ENODEV;
-
-	if (!(msi->flags & KVM_MSI_VALID_DEVID))
-		return -EINVAL;
-
-	address = (u64)msi->address_hi << 32 | msi->address_lo;
+	its = vgic_msi_to_its(kvm, msi);
+	if (IS_ERR(its))
+		return PTR_ERR(its);
 
-	kvm_io_dev = kvm_io_bus_get_dev(kvm, KVM_MMIO_BUS, address);
-	if (!kvm_io_dev)
-		return -EINVAL;
-
-	iodev = vgic_get_its_iodev(kvm_io_dev);
-	if (!iodev)
-		return -EINVAL;
-
-	mutex_lock(&iodev->its->its_lock);
-	ret = vgic_its_trigger_msi(kvm, iodev->its, msi->devid, msi->data);
-	mutex_unlock(&iodev->its->its_lock);
+	mutex_lock(&its->its_lock);
+	ret = vgic_its_trigger_msi(kvm, its, msi->devid, msi->data);
+	mutex_unlock(&its->its_lock);
 
 	if (ret < 0)
 		return ret;
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 4f8aecb07ae6..0ac85045c0c7 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -237,4 +237,8 @@ static inline int vgic_v3_max_apr_idx(struct kvm_vcpu *vcpu)
 	}
 }
 
+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);
+
 #endif
-- 
2.14.2

[PULL 06/27] KVM: arm/arm64: vITS: Add a helper to update the affinity of an LPI

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

In order to help integrating the vITS code with GICv4, let's add
a new helper that deals with updating the affinity of an LPI,
which will later be augmented with super duper extra GICv4
goodness.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 1de4e68ef1b6..09accdfed189 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -336,6 +336,15 @@ static int vgic_copy_lpi_list(struct kvm_vcpu *vcpu, u32 **intid_ptr)
 	return i;
 }
 
+static int update_affinity(struct vgic_irq *irq, struct kvm_vcpu *vcpu)
+{
+	spin_lock(&irq->irq_lock);
+	irq->target_vcpu = vcpu;
+	spin_unlock(&irq->irq_lock);
+
+	return 0;
+}
+
 /*
  * Promotes the ITS view of affinity of an ITTE (which redistributor this LPI
  * is targeting) to the VGIC's view, which deals with target VCPUs.
@@ -350,10 +359,7 @@ static void update_affinity_ite(struct kvm *kvm, struct its_ite *ite)
 		return;
 
 	vcpu = kvm_get_vcpu(kvm, ite->collection->target_addr);
-
-	spin_lock(&ite->irq->irq_lock);
-	ite->irq->target_vcpu = vcpu;
-	spin_unlock(&ite->irq->irq_lock);
+	update_affinity(ite->irq, vcpu);
 }
 
 /*
@@ -696,11 +702,7 @@ static int vgic_its_cmd_handle_movi(struct kvm *kvm, struct vgic_its *its,
 	ite->collection = collection;
 	vcpu = kvm_get_vcpu(kvm, collection->target_addr);
 
-	spin_lock(&ite->irq->irq_lock);
-	ite->irq->target_vcpu = vcpu;
-	spin_unlock(&ite->irq->irq_lock);
-
-	return 0;
+	return update_affinity(ite->irq, vcpu);
 }
 
 /*
-- 
2.14.2

[PULL 07/27] KVM: arm/arm64: GICv4: Add property field and per-VM predicate

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

Add a new has_gicv4 field in the global VGIC state that indicates
whether the HW is GICv4 capable, as a per-VM predicate indicating
if there is a possibility for a VM to support direct injection
(the above being true and the VM having an ITS).

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 include/kvm/arm_vgic.h           | 3 +++
 virt/kvm/arm/vgic/vgic-mmio-v3.c | 5 +++++
 virt/kvm/arm/vgic/vgic.h         | 2 ++
 3 files changed, 10 insertions(+)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 53f631bdec75..ba9fb450aa1b 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -73,6 +73,9 @@ struct vgic_global {
 	/* Only needed for the legacy KVM_CREATE_IRQCHIP */
 	bool			can_emulate_gicv2;
 
+	/* Hardware has GICv4? */
+	bool			has_gicv4;
+
 	/* GIC system register CPU interface */
 	struct static_key_false gicv3_cpuif;
 
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 83786108829e..671fe81f8e1d 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -54,6 +54,11 @@ bool vgic_has_its(struct kvm *kvm)
 	return dist->has_its;
 }
 
+bool vgic_supports_direct_msis(struct kvm *kvm)
+{
+	return kvm_vgic_global_state.has_gicv4 && vgic_has_its(kvm);
+}
+
 static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu,
 					    gpa_t addr, unsigned int len)
 {
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 0ac85045c0c7..67509b203cf5 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -241,4 +241,6 @@ 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);
 
+bool vgic_supports_direct_msis(struct kvm *kvm);
+
 #endif
-- 
2.14.2

[PULL 08/27] KVM: arm/arm64: GICv4: Add init/teardown of the per-VM vPE irq domain

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

In order to control the GICv4 view of virtual CPUs, we rely
on an irqdomain allocated for that purpose. Let's add a couple
of helpers to that effect.

At the same time, the vgic data structures gain new fields to
track all this... erm... wonderful stuff.

The way we hook into the vgic init is slightly convoluted. We
need the vgic to be initialized (in order to guarantee that
the number of vcpus is now fixed), and we must have a vITS
(otherwise this is all very pointless). So we end-up calling
the init from both vgic_init and vgic_its_create.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm/kvm/Makefile         |  1 +
 arch/arm64/kvm/Makefile       |  1 +
 include/kvm/arm_vgic.h        | 19 ++++++++++
 virt/kvm/arm/vgic/vgic-init.c |  9 +++++
 virt/kvm/arm/vgic/vgic-its.c  |  8 +++++
 virt/kvm/arm/vgic/vgic-v4.c   | 83 +++++++++++++++++++++++++++++++++++++++++++
 virt/kvm/arm/vgic/vgic.h      |  2 ++
 7 files changed, 123 insertions(+)
 create mode 100644 virt/kvm/arm/vgic/vgic-v4.c

diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
index d9beee652d36..0a1dd2cdb928 100644
--- a/arch/arm/kvm/Makefile
+++ b/arch/arm/kvm/Makefile
@@ -31,6 +31,7 @@ obj-y += $(KVM)/arm/vgic/vgic-init.o
 obj-y += $(KVM)/arm/vgic/vgic-irqfd.o
 obj-y += $(KVM)/arm/vgic/vgic-v2.o
 obj-y += $(KVM)/arm/vgic/vgic-v3.o
+obj-y += $(KVM)/arm/vgic/vgic-v4.o
 obj-y += $(KVM)/arm/vgic/vgic-mmio.o
 obj-y += $(KVM)/arm/vgic/vgic-mmio-v2.o
 obj-y += $(KVM)/arm/vgic/vgic-mmio-v3.o
diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile
index 5d9810086c25..c30fd388ef80 100644
--- a/arch/arm64/kvm/Makefile
+++ b/arch/arm64/kvm/Makefile
@@ -26,6 +26,7 @@ kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-init.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-irqfd.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-v2.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-v3.o
+kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-v4.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-mmio.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-mmio-v2.o
 kvm-$(CONFIG_KVM_ARM_HOST) += $(KVM)/arm/vgic/vgic-mmio-v3.o
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index ba9fb450aa1b..7eeb6c2a2f9c 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -26,6 +26,8 @@
 #include <linux/list.h>
 #include <linux/jump_label.h>
 
+#include <linux/irqchip/arm-gic-v4.h>
+
 #define VGIC_V3_MAX_CPUS	255
 #define VGIC_V2_MAX_CPUS	8
 #define VGIC_NR_IRQS_LEGACY     256
@@ -236,6 +238,15 @@ struct vgic_dist {
 
 	/* used by vgic-debug */
 	struct vgic_state_iter *iter;
+
+	/*
+	 * GICv4 ITS per-VM data, containing the IRQ domain, the VPE
+	 * array, the property table pointer as well as allocation
+	 * data. This essentially ties the Linux IRQ core and ITS
+	 * together, and avoids leaking KVM's data structures anywhere
+	 * else.
+	 */
+	struct its_vm		its_vm;
 };
 
 struct vgic_v2_cpu_if {
@@ -254,6 +265,14 @@ struct vgic_v3_cpu_if {
 	u32		vgic_ap0r[4];
 	u32		vgic_ap1r[4];
 	u64		vgic_lr[VGIC_V3_MAX_LRS];
+
+	/*
+	 * GICv4 ITS per-VPE data, containing the doorbell IRQ, the
+	 * pending table pointer, the its_vm pointer and a few other
+	 * HW specific things. As for the its_vm structure, this is
+	 * linking the Linux IRQ subsystem and the ITS together.
+	 */
+	struct its_vpe	its_vpe;
 };
 
 struct vgic_cpu {
diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 5801261f3add..40be908da238 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -285,6 +285,12 @@ int vgic_init(struct kvm *kvm)
 	if (ret)
 		goto out;
 
+	if (vgic_supports_direct_msis(kvm)) {
+		ret = vgic_v4_init(kvm);
+		if (ret)
+			goto out;
+	}
+
 	kvm_for_each_vcpu(i, vcpu, kvm)
 		kvm_vgic_vcpu_enable(vcpu);
 
@@ -320,6 +326,9 @@ static void kvm_vgic_dist_destroy(struct kvm *kvm)
 
 	kfree(dist->spis);
 	dist->nr_spis = 0;
+
+	if (vgic_supports_direct_msis(kvm))
+		vgic_v4_teardown(kvm);
 }
 
 void kvm_vgic_vcpu_destroy(struct kvm_vcpu *vcpu)
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 09accdfed189..54f81eb24a07 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -1638,6 +1638,14 @@ static int vgic_its_create(struct kvm_device *dev, u32 type)
 	if (!its)
 		return -ENOMEM;
 
+	if (vgic_initialized(dev->kvm)) {
+		int ret = vgic_v4_init(dev->kvm);
+		if (ret) {
+			kfree(its);
+			return ret;
+		}
+	}
+
 	mutex_init(&its->its_lock);
 	mutex_init(&its->cmd_lock);
 
diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
new file mode 100644
index 000000000000..c794f0cef09e
--- /dev/null
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2017 ARM Ltd.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/kvm_host.h>
+
+#include "vgic.h"
+
+/**
+ * vgic_v4_init - Initialize the GICv4 data structures
+ * @kvm:	Pointer to the VM being initialized
+ *
+ * We may be called each time a vITS is created, or when the
+ * vgic is initialized. This relies on kvm->lock to be
+ * held. In both cases, the number of vcpus should now be
+ * fixed.
+ */
+int vgic_v4_init(struct kvm *kvm)
+{
+	struct vgic_dist *dist = &kvm->arch.vgic;
+	struct kvm_vcpu *vcpu;
+	int i, nr_vcpus, ret;
+
+	if (dist->its_vm.vpes)
+		return 0;
+
+	nr_vcpus = atomic_read(&kvm->online_vcpus);
+
+	dist->its_vm.vpes = kzalloc(sizeof(*dist->its_vm.vpes) * nr_vcpus,
+				    GFP_KERNEL);
+	if (!dist->its_vm.vpes)
+		return -ENOMEM;
+
+	dist->its_vm.nr_vpes = nr_vcpus;
+
+	kvm_for_each_vcpu(i, vcpu, kvm)
+		dist->its_vm.vpes[i] = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe;
+
+	ret = its_alloc_vcpu_irqs(&dist->its_vm);
+	if (ret < 0) {
+		kvm_err("VPE IRQ allocation failure\n");
+		kfree(dist->its_vm.vpes);
+		dist->its_vm.nr_vpes = 0;
+		dist->its_vm.vpes = NULL;
+		return ret;
+	}
+
+	return ret;
+}
+
+/**
+ * vgic_v4_teardown - Free the GICv4 data structures
+ * @kvm:	Pointer to the VM being destroyed
+ *
+ * Relies on kvm->lock to be held.
+ */
+void vgic_v4_teardown(struct kvm *kvm)
+{
+	struct its_vm *its_vm = &kvm->arch.vgic.its_vm;
+
+	if (!its_vm->vpes)
+		return;
+
+	its_free_vcpu_irqs(its_vm);
+	kfree(its_vm->vpes);
+	its_vm->nr_vpes = 0;
+	its_vm->vpes = NULL;
+}
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 67509b203cf5..bf03a9648fbb 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -242,5 +242,7 @@ int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its,
 struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi);
 
 bool vgic_supports_direct_msis(struct kvm *kvm);
+int vgic_v4_init(struct kvm *kvm);
+void vgic_v4_teardown(struct kvm *kvm);
 
 #endif
-- 
2.14.2

[PULL 09/27] KVM: arm/arm64: GICv4: Wire mapping/unmapping of VLPIs in VFIO irq bypass

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

Let's use the irq bypass mechanism also used for x86 posted interrupts
to intercept the virtual PCIe endpoint configuration and establish our
LPI->VLPI mapping.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 include/kvm/arm_vgic.h      |   8 ++++
 virt/kvm/arm/arm.c          |   6 ++-
 virt/kvm/arm/vgic/vgic-v4.c | 104 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 116 insertions(+), 2 deletions(-)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 7eeb6c2a2f9c..2f750c770bf2 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -373,4 +373,12 @@ int kvm_vgic_setup_default_irq_routing(struct kvm *kvm);
 
 int kvm_vgic_set_owner(struct kvm_vcpu *vcpu, unsigned int intid, void *owner);
 
+struct kvm_kernel_irq_routing_entry;
+
+int kvm_vgic_v4_set_forwarding(struct kvm *kvm, int irq,
+			       struct kvm_kernel_irq_routing_entry *irq_entry);
+
+int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq,
+				 struct kvm_kernel_irq_routing_entry *irq_entry);
+
 #endif /* __KVM_ARM_VGIC_H */
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index e1e947fe9bc2..34a15c0c65ab 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -1471,7 +1471,8 @@ int kvm_arch_irq_bypass_add_producer(struct irq_bypass_consumer *cons,
 	struct kvm_kernel_irqfd *irqfd =
 		container_of(cons, struct kvm_kernel_irqfd, consumer);
 
-	return 0;
+	return kvm_vgic_v4_set_forwarding(irqfd->kvm, prod->irq,
+					  &irqfd->irq_entry);
 }
 void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
 				      struct irq_bypass_producer *prod)
@@ -1479,7 +1480,8 @@ void kvm_arch_irq_bypass_del_producer(struct irq_bypass_consumer *cons,
 	struct kvm_kernel_irqfd *irqfd =
 		container_of(cons, struct kvm_kernel_irqfd, consumer);
 
-	return;
+	kvm_vgic_v4_unset_forwarding(irqfd->kvm, prod->irq,
+				     &irqfd->irq_entry);
 }
 
 void kvm_arch_irq_bypass_stop(struct irq_bypass_consumer *cons)
diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index c794f0cef09e..2edfe23c8238 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -18,6 +18,7 @@
 #include <linux/interrupt.h>
 #include <linux/irqdomain.h>
 #include <linux/kvm_host.h>
+#include <linux/irqchip/arm-gic-v3.h>
 
 #include "vgic.h"
 
@@ -81,3 +82,106 @@ void vgic_v4_teardown(struct kvm *kvm)
 	its_vm->nr_vpes = 0;
 	its_vm->vpes = NULL;
 }
+
+static struct vgic_its *vgic_get_its(struct kvm *kvm,
+				     struct kvm_kernel_irq_routing_entry *irq_entry)
+{
+	struct kvm_msi msi  = (struct kvm_msi) {
+		.address_lo	= irq_entry->msi.address_lo,
+		.address_hi	= irq_entry->msi.address_hi,
+		.data		= irq_entry->msi.data,
+		.flags		= irq_entry->msi.flags,
+		.devid		= irq_entry->msi.devid,
+	};
+
+	return vgic_msi_to_its(kvm, &msi);
+}
+
+int kvm_vgic_v4_set_forwarding(struct kvm *kvm, int virq,
+			       struct kvm_kernel_irq_routing_entry *irq_entry)
+{
+	struct vgic_its *its;
+	struct vgic_irq *irq;
+	struct its_vlpi_map map;
+	int ret;
+
+	if (!vgic_supports_direct_msis(kvm))
+		return 0;
+
+	/*
+	 * Get the ITS, and escape early on error (not a valid
+	 * doorbell for any of our vITSs).
+	 */
+	its = vgic_get_its(kvm, irq_entry);
+	if (IS_ERR(its))
+		return 0;
+
+	mutex_lock(&its->its_lock);
+
+	/* Perform then actual DevID/EventID -> LPI translation. */
+	ret = vgic_its_resolve_lpi(kvm, its, irq_entry->msi.devid,
+				   irq_entry->msi.data, &irq);
+	if (ret)
+		goto out;
+
+	/*
+	 * Emit the mapping request. If it fails, the ITS probably
+	 * isn't v4 compatible, so let's silently bail out. Holding
+	 * the ITS lock should ensure that nothing can modify the
+	 * target vcpu.
+	 */
+	map = (struct its_vlpi_map) {
+		.vm		= &kvm->arch.vgic.its_vm,
+		.vpe		= &irq->target_vcpu->arch.vgic_cpu.vgic_v3.its_vpe,
+		.vintid		= irq->intid,
+		.properties	= ((irq->priority & 0xfc) |
+				   (irq->enabled ? LPI_PROP_ENABLED : 0) |
+				   LPI_PROP_GROUP1),
+		.db_enabled	= true,
+	};
+
+	ret = its_map_vlpi(virq, &map);
+	if (ret)
+		goto out;
+
+	irq->hw		= true;
+	irq->host_irq	= virq;
+
+out:
+	mutex_unlock(&its->its_lock);
+	return ret;
+}
+
+int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int virq,
+				 struct kvm_kernel_irq_routing_entry *irq_entry)
+{
+	struct vgic_its *its;
+	struct vgic_irq *irq;
+	int ret;
+
+	if (!vgic_supports_direct_msis(kvm))
+		return 0;
+
+	/*
+	 * Get the ITS, and escape early on error (not a valid
+	 * doorbell for any of our vITSs).
+	 */
+	its = vgic_get_its(kvm, irq_entry);
+	if (IS_ERR(its))
+		return 0;
+
+	mutex_lock(&its->its_lock);
+
+	ret = vgic_its_resolve_lpi(kvm, its, irq_entry->msi.devid,
+				   irq_entry->msi.data, &irq);
+	if (ret)
+		goto out;
+
+	WARN_ON(!(irq->hw && irq->host_irq == virq));
+	irq->hw = false;
+	ret = its_unmap_vlpi(virq);
+
+out:
+	mutex_unlock(&its->its_lock);
+	return ret;
+}
-- 
2.14.2

[PULL 10/27] KVM: arm/arm64: GICv4: Handle INT command applied to a VLPI

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

If the guest issues an INT command targetting a VLPI, let's
call into the irq_set_irqchip_state() helper to make it pending
on the physical side.

This works just as well if userspace decides to inject an interrupt
using the normal userspace API...

Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 54f81eb24a07..590f794b7330 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -581,6 +581,10 @@ static int vgic_its_trigger_msi(struct kvm *kvm, struct vgic_its *its,
 	if (err)
 		return err;
 
+	if (irq->hw)
+		return irq_set_irqchip_state(irq->host_irq,
+					     IRQCHIP_STATE_PENDING, true);
+
 	spin_lock_irqsave(&irq->irq_lock, flags);
 	irq->pending_latch = true;
 	vgic_queue_irq_unlock(kvm, irq, flags);
-- 
2.14.2

[PULL 11/27] KVM: arm/arm64: GICv4: Unmap VLPI when freeing an LPI

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

When freeing an LPI (on a DISCARD command, for example), we need
to unmap the VLPI down to the physical ITS level.

Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 590f794b7330..ad14af8a4412 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -631,8 +631,12 @@ static void its_free_ite(struct kvm *kvm, struct its_ite *ite)
 	list_del(&ite->ite_list);
 
 	/* This put matches the get in vgic_add_lpi. */
-	if (ite->irq)
+	if (ite->irq) {
+		if (ite->irq->hw)
+			WARN_ON(its_unmap_vlpi(ite->irq->host_irq));
+
 		vgic_put_irq(kvm, ite->irq);
+	}
 
 	kfree(ite);
 }
-- 
2.14.2

[PULL 12/27] KVM: arm/arm64: GICv4: Propagate affinity changes to the physical ITS

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

When the guest issues an affinity change, we need to tell the physical
ITS that we're now targetting a new vcpu.  This is done by extracting
the current mapping, updating the target, and reapplying the mapping.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index ad14af8a4412..80bea7021e2e 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -338,11 +338,25 @@ static int vgic_copy_lpi_list(struct kvm_vcpu *vcpu, u32 **intid_ptr)
 
 static int update_affinity(struct vgic_irq *irq, struct kvm_vcpu *vcpu)
 {
+	int ret = 0;
+
 	spin_lock(&irq->irq_lock);
 	irq->target_vcpu = vcpu;
 	spin_unlock(&irq->irq_lock);
 
-	return 0;
+	if (irq->hw) {
+		struct its_vlpi_map map;
+
+		ret = its_get_vlpi(irq->host_irq, &map);
+		if (ret)
+			return ret;
+
+		map.vpe = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe;
+
+		ret = its_map_vlpi(irq->host_irq, &map);
+	}
+
+	return ret;
 }
 
 /*
-- 
2.14.2

[PULL 13/27] KVM: arm/arm64: GICv4: Handle CLEAR applied to a VLPI

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

Handling CLEAR is pretty easy. Just ask the ITS driver to clear
the corresponding pending bit (which will turn into a CLEAR
command on the physical side).

Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 80bea7021e2e..15e79285380d 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -1091,6 +1091,10 @@ static int vgic_its_cmd_handle_clear(struct kvm *kvm, struct vgic_its *its,
 
 	ite->irq->pending_latch = false;
 
+	if (ite->irq->hw)
+		return irq_set_irqchip_state(ite->irq->host_irq,
+					     IRQCHIP_STATE_PENDING, false);
+
 	return 0;
 }
 
-- 
2.14.2

[PULL 14/27] KVM: arm/arm64: GICv4: Handle MOVALL applied to a vPE

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

The current implementation of MOVALL doesn't allow us to call
into the core ITS code as we hold a number of spinlocks.

Let's try a method used in other parts of the code, were we copy
the intids of the candicate interrupts, and then do whatever
we need to do with them outside of the critical section.

This allows us to move the interrupts one by one, at the expense
of a bit of CPU time. Who cares? MOVALL is such a stupid command
anyway...

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 15e79285380d..78d11aed1e17 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -1169,11 +1169,12 @@ static int vgic_its_cmd_handle_invall(struct kvm *kvm, struct vgic_its *its,
 static int vgic_its_cmd_handle_movall(struct kvm *kvm, struct vgic_its *its,
 				      u64 *its_cmd)
 {
-	struct vgic_dist *dist = &kvm->arch.vgic;
 	u32 target1_addr = its_cmd_get_target_addr(its_cmd);
 	u32 target2_addr = its_cmd_mask_field(its_cmd, 3, 16, 32);
 	struct kvm_vcpu *vcpu1, *vcpu2;
 	struct vgic_irq *irq;
+	u32 *intids;
+	int irq_count, i;
 
 	if (target1_addr >= atomic_read(&kvm->online_vcpus) ||
 	    target2_addr >= atomic_read(&kvm->online_vcpus))
@@ -1185,19 +1186,19 @@ static int vgic_its_cmd_handle_movall(struct kvm *kvm, struct vgic_its *its,
 	vcpu1 = kvm_get_vcpu(kvm, target1_addr);
 	vcpu2 = kvm_get_vcpu(kvm, target2_addr);
 
-	spin_lock(&dist->lpi_list_lock);
+	irq_count = vgic_copy_lpi_list(vcpu1, &intids);
+	if (irq_count < 0)
+		return irq_count;
 
-	list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
-		spin_lock(&irq->irq_lock);
+	for (i = 0; i < irq_count; i++) {
+		irq = vgic_get_irq(kvm, NULL, intids[i]);
 
-		if (irq->target_vcpu == vcpu1)
-			irq->target_vcpu = vcpu2;
+		update_affinity(irq, vcpu2);
 
-		spin_unlock(&irq->irq_lock);
+		vgic_put_irq(kvm, irq);
 	}
 
-	spin_unlock(&dist->lpi_list_lock);
-
+	kfree(intids);
 	return 0;
 }
 
-- 
2.14.2

[PULL 15/27] KVM: arm/arm64: GICv4: Propagate property updates to VLPIs

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

Upon updating a property, we propagate it all the way to the physical
ITS, and ask for an INV command to be executed there.

Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 78d11aed1e17..4768a0e21cc5 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -297,6 +297,9 @@ static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
 		spin_unlock_irqrestore(&irq->irq_lock, flags);
 	}
 
+	if (irq->hw)
+		return its_prop_update_vlpi(irq->host_irq, prop, true);
+
 	return 0;
 }
 
-- 
2.14.2

[PULL 16/27] KVM: arm/arm64: GICv4: Handle INVALL applied to a vPE

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

There is no need to perform an INV for each interrupt when updating
multiple interrupts.  Instead, we can rely on the final VINVALL that
gets sent to the ITS to do the work for all of them.

Acked-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index 4768a0e21cc5..bf571f6d2b32 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -38,7 +38,7 @@ static int vgic_its_save_tables_v0(struct vgic_its *its);
 static int vgic_its_restore_tables_v0(struct vgic_its *its);
 static int vgic_its_commit_v0(struct vgic_its *its);
 static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
-			     struct kvm_vcpu *filter_vcpu);
+			     struct kvm_vcpu *filter_vcpu, bool needs_inv);
 
 /*
  * Creates a new (reference to a) struct vgic_irq for a given LPI.
@@ -106,7 +106,7 @@ static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid,
 	 * However we only have those structs for mapped IRQs, so we read in
 	 * the respective config data from memory here upon mapping the LPI.
 	 */
-	ret = update_lpi_config(kvm, irq, NULL);
+	ret = update_lpi_config(kvm, irq, NULL, false);
 	if (ret)
 		return ERR_PTR(ret);
 
@@ -273,7 +273,7 @@ static struct its_collection *find_collection(struct vgic_its *its, int coll_id)
  * VCPU. Unconditionally applies if filter_vcpu is NULL.
  */
 static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
-			     struct kvm_vcpu *filter_vcpu)
+			     struct kvm_vcpu *filter_vcpu, bool needs_inv)
 {
 	u64 propbase = GICR_PROPBASER_ADDRESS(kvm->arch.vgic.propbaser);
 	u8 prop;
@@ -298,7 +298,7 @@ static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
 	}
 
 	if (irq->hw)
-		return its_prop_update_vlpi(irq->host_irq, prop, true);
+		return its_prop_update_vlpi(irq->host_irq, prop, needs_inv);
 
 	return 0;
 }
@@ -1117,7 +1117,7 @@ static int vgic_its_cmd_handle_inv(struct kvm *kvm, struct vgic_its *its,
 	if (!ite)
 		return E_ITS_INV_UNMAPPED_INTERRUPT;
 
-	return update_lpi_config(kvm, ite->irq, NULL);
+	return update_lpi_config(kvm, ite->irq, NULL, true);
 }
 
 /*
@@ -1152,12 +1152,15 @@ static int vgic_its_cmd_handle_invall(struct kvm *kvm, struct vgic_its *its,
 		irq = vgic_get_irq(kvm, NULL, intids[i]);
 		if (!irq)
 			continue;
-		update_lpi_config(kvm, irq, vcpu);
+		update_lpi_config(kvm, irq, vcpu, false);
 		vgic_put_irq(kvm, irq);
 	}
 
 	kfree(intids);
 
+	if (vcpu->arch.vgic_cpu.vgic_v3.its_vpe.its_vm)
+		its_invall_vpe(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe);
+
 	return 0;
 }
 
-- 
2.14.2

[PULL 17/27] KVM: arm/arm64: GICv4: Use pending_last as a scheduling hint

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

When a vPE exits, the pending_last flag is set when there are pending
VLPIs stored in the pending table. Similarily, this flag will be set
when a doorbell interrupt fires, as it indicates the same condition.

Let's update kvm_vgic_vcpu_pending_irq() to account for that
flag as well, making a vcpu runnable when set.

Acked-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
index a05a5700910b..d29e91215366 100644
--- a/virt/kvm/arm/vgic/vgic.c
+++ b/virt/kvm/arm/vgic/vgic.c
@@ -781,6 +781,9 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
 	if (!vcpu->kvm->arch.vgic.enabled)
 		return false;
 
+	if (vcpu->arch.vgic_cpu.vgic_v3.its_vpe.pending_last)
+		return true;
+
 	spin_lock_irqsave(&vgic_cpu->ap_list_lock, flags);
 
 	list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) {
-- 
2.14.2

[PULL 18/27] KVM: arm/arm64: GICv4: Add doorbell interrupt handling

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

When a vPE is not running, a VLPI being made pending results in a
doorbell interrupt being delivered. Let's handle this interrupt
and update the pending_last flag that indicates that VLPIs are
pending. The corresponding vcpu is also kicked into action.

Special care is taken to prevent the doorbell from being enabled
at request time (this is controlled separately), and to make
the disabling on the interrupt non-lazy.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-v4.c | 48 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index 2edfe23c8238..796e00c77903 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -16,12 +16,24 @@
  */
 
 #include <linux/interrupt.h>
+#include <linux/irq.h>
 #include <linux/irqdomain.h>
 #include <linux/kvm_host.h>
 #include <linux/irqchip/arm-gic-v3.h>
 
 #include "vgic.h"
 
+static irqreturn_t vgic_v4_doorbell_handler(int irq, void *info)
+{
+	struct kvm_vcpu *vcpu = info;
+
+	vcpu->arch.vgic_cpu.vgic_v3.its_vpe.pending_last = true;
+	kvm_make_request(KVM_REQ_IRQ_PENDING, vcpu);
+	kvm_vcpu_kick(vcpu);
+
+	return IRQ_HANDLED;
+}
+
 /**
  * vgic_v4_init - Initialize the GICv4 data structures
  * @kvm:	Pointer to the VM being initialized
@@ -61,6 +73,33 @@ int vgic_v4_init(struct kvm *kvm)
 		return ret;
 	}
 
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		int irq = dist->its_vm.vpes[i]->irq;
+
+		/*
+		 * Don't automatically enable the doorbell, as we're
+		 * flipping it back and forth when the vcpu gets
+		 * blocked. Also disable the lazy disabling, as the
+		 * doorbell could kick us out of the guest too
+		 * early...
+		 */
+		irq_set_status_flags(irq, IRQ_NOAUTOEN | IRQ_DISABLE_UNLAZY);
+		ret = request_irq(irq, vgic_v4_doorbell_handler,
+				  0, "vcpu", vcpu);
+		if (ret) {
+			kvm_err("failed to allocate vcpu IRQ%d\n", irq);
+			/*
+			 * Trick: adjust the number of vpes so we know
+			 * how many to nuke on teardown...
+			 */
+			dist->its_vm.nr_vpes = i;
+			break;
+		}
+	}
+
+	if (ret)
+		vgic_v4_teardown(kvm);
+
 	return ret;
 }
 
@@ -73,10 +112,19 @@ int vgic_v4_init(struct kvm *kvm)
 void vgic_v4_teardown(struct kvm *kvm)
 {
 	struct its_vm *its_vm = &kvm->arch.vgic.its_vm;
+	int i;
 
 	if (!its_vm->vpes)
 		return;
 
+	for (i = 0; i < its_vm->nr_vpes; i++) {
+		struct kvm_vcpu *vcpu = kvm_get_vcpu(kvm, i);
+		int irq = its_vm->vpes[i]->irq;
+
+		irq_clear_status_flags(irq, IRQ_NOAUTOEN | IRQ_DISABLE_UNLAZY);
+		free_irq(irq, vcpu);
+	}
+
 	its_free_vcpu_irqs(its_vm);
 	kfree(its_vm->vpes);
 	its_vm->nr_vpes = 0;
-- 
2.14.2

[PULL 19/27] KVM: arm/arm64: GICv4: Use the doorbell interrupt as an unblocking source

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

The doorbell interrupt is only useful if the vcpu is blocked on WFI.
In all other cases, recieving a doorbell interrupt is just a waste
of cycles.

So let's only enable the doorbell if a vcpu is getting blocked,
and disable it when it is unblocked. This is very similar to
what we're doing for the background timer.

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 include/kvm/arm_vgic.h      |  3 +++
 virt/kvm/arm/arm.c          |  2 ++
 virt/kvm/arm/vgic/vgic-v4.c | 18 ++++++++++++++++++
 3 files changed, 23 insertions(+)

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 2f750c770bf2..8c896540a72c 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -381,4 +381,7 @@ int kvm_vgic_v4_set_forwarding(struct kvm *kvm, int irq,
 int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq,
 				 struct kvm_kernel_irq_routing_entry *irq_entry);
 
+void kvm_vgic_v4_enable_doorbell(struct kvm_vcpu *vcpu);
+void kvm_vgic_v4_disable_doorbell(struct kvm_vcpu *vcpu);
+
 #endif /* __KVM_ARM_VGIC_H */
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 34a15c0c65ab..01e575b9f78b 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -315,11 +315,13 @@ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
 {
 	kvm_timer_schedule(vcpu);
+	kvm_vgic_v4_enable_doorbell(vcpu);
 }
 
 void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu)
 {
 	kvm_timer_unschedule(vcpu);
+	kvm_vgic_v4_disable_doorbell(vcpu);
 }
 
 int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index 796e00c77903..1375a53054b9 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -233,3 +233,21 @@ int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int virq,
 	mutex_unlock(&its->its_lock);
 	return ret;
 }
+
+void kvm_vgic_v4_enable_doorbell(struct kvm_vcpu *vcpu)
+{
+	if (vgic_supports_direct_msis(vcpu->kvm)) {
+		int irq = vcpu->arch.vgic_cpu.vgic_v3.its_vpe.irq;
+		if (irq)
+			enable_irq(irq);
+	}
+}
+
+void kvm_vgic_v4_disable_doorbell(struct kvm_vcpu *vcpu)
+{
+	if (vgic_supports_direct_msis(vcpu->kvm)) {
+		int irq = vcpu->arch.vgic_cpu.vgic_v3.its_vpe.irq;
+		if (irq)
+			disable_irq(irq);
+	}
+}
-- 
2.14.2

[PULL 20/27] KVM: arm/arm64: GICv4: Hook vPE scheduling into vgic flush/sync

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

The redistributor needs to be told which vPE is about to be run,
and tells us whether there is any pending VLPI on exit.

Let's add the scheduling calls to the vgic flush/sync functions,
allowing the VLPIs to be delivered to the guest.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-v4.c | 39 +++++++++++++++++++++++++++++++++++++++
 virt/kvm/arm/vgic/vgic.c    |  4 ++++
 virt/kvm/arm/vgic/vgic.h    |  2 ++
 3 files changed, 45 insertions(+)

diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index 1375a53054b9..c9cec01008c2 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -131,6 +131,45 @@ void vgic_v4_teardown(struct kvm *kvm)
 	its_vm->vpes = NULL;
 }
 
+int vgic_v4_sync_hwstate(struct kvm_vcpu *vcpu)
+{
+	if (!vgic_supports_direct_msis(vcpu->kvm))
+		return 0;
+
+	return its_schedule_vpe(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe, false);
+}
+
+int vgic_v4_flush_hwstate(struct kvm_vcpu *vcpu)
+{
+	int irq = vcpu->arch.vgic_cpu.vgic_v3.its_vpe.irq;
+	int err;
+
+	if (!vgic_supports_direct_msis(vcpu->kvm))
+		return 0;
+
+	/*
+	 * Before making the VPE resident, make sure the redistributor
+	 * corresponding to our current CPU expects us here. See the
+	 * doc in drivers/irqchip/irq-gic-v4.c to understand how this
+	 * turns into a VMOVP command at the ITS level.
+	 */
+	err = irq_set_affinity(irq, cpumask_of(smp_processor_id()));
+	if (err)
+		return err;
+
+	err = its_schedule_vpe(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe, true);
+	if (err)
+		return err;
+
+	/*
+	 * Now that the VPE is resident, let's get rid of a potential
+	 * doorbell interrupt that would still be pending.
+	 */
+	err = irq_set_irqchip_state(irq, IRQCHIP_STATE_PENDING, false);
+
+	return err;
+}
+
 static struct vgic_its *vgic_get_its(struct kvm *kvm,
 				     struct kvm_kernel_irq_routing_entry *irq_entry)
 {
diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
index d29e91215366..b168a328a9e0 100644
--- a/virt/kvm/arm/vgic/vgic.c
+++ b/virt/kvm/arm/vgic/vgic.c
@@ -718,6 +718,8 @@ void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
 {
 	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
 
+	WARN_ON(vgic_v4_sync_hwstate(vcpu));
+
 	/* An empty ap_list_head implies used_lrs == 0 */
 	if (list_empty(&vcpu->arch.vgic_cpu.ap_list_head))
 		return;
@@ -730,6 +732,8 @@ void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
 /* Flush our emulation state into the GIC hardware before entering the guest. */
 void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
 {
+	WARN_ON(vgic_v4_flush_hwstate(vcpu));
+
 	/*
 	 * If there are no virtual interrupts active or pending for this
 	 * VCPU, then there is no work to do and we can bail out without
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index bf03a9648fbb..efbcf8f96f9c 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -244,5 +244,7 @@ struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi);
 bool vgic_supports_direct_msis(struct kvm *kvm);
 int vgic_v4_init(struct kvm *kvm);
 void vgic_v4_teardown(struct kvm *kvm);
+int vgic_v4_sync_hwstate(struct kvm_vcpu *vcpu);
+int vgic_v4_flush_hwstate(struct kvm_vcpu *vcpu);
 
 #endif
-- 
2.14.2

[PULL 21/27] KVM: arm/arm64: GICv4: Enable virtual cpuif if VLPIs can be delivered

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

In order for VLPIs to be delivered to the guest, we must make sure that
the virtual cpuif is always enabled, irrespective of the presence of
virtual interrupt in the LRs.

Acked-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/hyp/vgic-v3-sr.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c
index 91728faa13fd..f5c3d6d7019e 100644
--- a/virt/kvm/arm/hyp/vgic-v3-sr.c
+++ b/virt/kvm/arm/hyp/vgic-v3-sr.c
@@ -258,7 +258,8 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
 			cpu_if->vgic_ap1r[0] = __vgic_v3_read_ap1rn(0);
 		}
 	} else {
-		if (static_branch_unlikely(&vgic_v3_cpuif_trap))
+		if (static_branch_unlikely(&vgic_v3_cpuif_trap) ||
+		    cpu_if->its_vpe.its_vm)
 			write_gicreg(0, ICH_HCR_EL2);
 
 		cpu_if->vgic_elrsr = 0xffff;
@@ -337,9 +338,11 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
 		/*
 		 * If we need to trap system registers, we must write
 		 * ICH_HCR_EL2 anyway, even if no interrupts are being
-		 * injected,
+		 * injected. Same thing if GICv4 is used, as VLPI
+		 * delivery is gated by ICH_HCR_EL2.En.
 		 */
-		if (static_branch_unlikely(&vgic_v3_cpuif_trap))
+		if (static_branch_unlikely(&vgic_v3_cpuif_trap) ||
+		    cpu_if->its_vpe.its_vm)
 			write_gicreg(cpu_if->vgic_hcr, ICH_HCR_EL2);
 	}
 
-- 
2.14.2

[PULL 22/27] KVM: arm/arm64: GICv4: Prevent a VM using GICv4 from being saved

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

The GICv4 architecture doesn't make it easy for save/restore to
work, as it doesn't give any guarantee that the pending state
is written into the pending table.

So let's not take any chance, and let's return an error if
we encounter any LPI that has the HW bit set. In order for
userspace to distinguish this error from other failure modes,
use -EACCES as an error code.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 Documentation/virtual/kvm/devices/arm-vgic-its.txt | 2 ++
 virt/kvm/arm/vgic/vgic-its.c                       | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/Documentation/virtual/kvm/devices/arm-vgic-its.txt b/Documentation/virtual/kvm/devices/arm-vgic-its.txt
index 8d5830eab26a..4f0c9fc40365 100644
--- a/Documentation/virtual/kvm/devices/arm-vgic-its.txt
+++ b/Documentation/virtual/kvm/devices/arm-vgic-its.txt
@@ -64,6 +64,8 @@ Groups:
     -EINVAL: Inconsistent restored data
     -EFAULT: Invalid guest ram access
     -EBUSY:  One or more VCPUS are running
+    -EACCES: The virtual ITS is backed by a physical GICv4 ITS, and the
+	     state is not available
 
   KVM_DEV_ARM_VGIC_GRP_ITS_REGS
   Attributes:
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index bf571f6d2b32..b8c1b724ba3e 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -1995,6 +1995,15 @@ static int vgic_its_save_itt(struct vgic_its *its, struct its_device *device)
 	list_for_each_entry(ite, &device->itt_head, ite_list) {
 		gpa_t gpa = base + ite->event_id * ite_esz;
 
+		/*
+		 * If an LPI carries the HW bit, this means that this
+		 * interrupt is controlled by GICv4, and we do not
+		 * have direct access to that state. Let's simply fail
+		 * the save operation...
+		 */
+		if (ite->irq->hw)
+			return -EACCES;
+
 		ret = vgic_its_save_ite(its, device, ite, gpa, ite_esz);
 		if (ret)
 			return ret;
-- 
2.14.2

[PULL 23/27] KVM: arm/arm64: GICv4: Prevent userspace from changing doorbell affinity

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

We so far allocate the doorbell interrupts without taking any
special measure regarding the affinity of these interrupts. We
simply move them around as required when the vcpu gets scheduled
on a different CPU.

But that's counting without userspace (and the evil irqbalance) that
can try and move the VPE interrupt around, causing the ITS code
to emit VMOVP commands and remap the doorbell to another redistributor.
Worse, this can happen while the vcpu is running, causing all kind
of trouble if the VPE is already resident, and we end-up in UNPRED
territory.

So let's take a definitive action and prevent userspace from messing
with us. This is just a matter of adding IRQ_NO_BALANCING to the
set of flags we already have, letting the kernel in sole control
of the affinity.

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-v4.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index c9cec01008c2..bf874dd01fc0 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -23,6 +23,8 @@
 
 #include "vgic.h"
 
+#define DB_IRQ_FLAGS	(IRQ_NOAUTOEN | IRQ_DISABLE_UNLAZY | IRQ_NO_BALANCING)
+
 static irqreturn_t vgic_v4_doorbell_handler(int irq, void *info)
 {
 	struct kvm_vcpu *vcpu = info;
@@ -83,7 +85,7 @@ int vgic_v4_init(struct kvm *kvm)
 		 * doorbell could kick us out of the guest too
 		 * early...
 		 */
-		irq_set_status_flags(irq, IRQ_NOAUTOEN | IRQ_DISABLE_UNLAZY);
+		irq_set_status_flags(irq, DB_IRQ_FLAGS);
 		ret = request_irq(irq, vgic_v4_doorbell_handler,
 				  0, "vcpu", vcpu);
 		if (ret) {
@@ -121,7 +123,7 @@ void vgic_v4_teardown(struct kvm *kvm)
 		struct kvm_vcpu *vcpu = kvm_get_vcpu(kvm, i);
 		int irq = its_vm->vpes[i]->irq;
 
-		irq_clear_status_flags(irq, IRQ_NOAUTOEN | IRQ_DISABLE_UNLAZY);
+		irq_clear_status_flags(irq, DB_IRQ_FLAGS);
 		free_irq(irq, vcpu);
 	}
 
-- 
2.14.2

[PULL 24/27] KVM: arm/arm64: GICv4: Enable VLPI support

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

All it takes is the has_v4 flag to be set in gic_kvm_info
as well as "kvm-arm.vgic_v4_enable=1" being passed on the
command line for GICv4 to be enabled in KVM.

Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 Documentation/admin-guide/kernel-parameters.txt |  4 ++++
 virt/kvm/arm/vgic/vgic-v3.c                     | 14 ++++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 3daa0a590236..6f897a4c8281 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1881,6 +1881,10 @@
 			[KVM,ARM] Trap guest accesses to GICv3 common
 			system registers
 
+	kvm-arm.vgic_v4_enable=
+			[KVM,ARM] Allow use of GICv4 for direct injection of
+			LPIs.
+
 	kvm-intel.ept=	[KVM,Intel] Disable extended page tables
 			(virtualized MMU) support on capable Intel chips.
 			Default is 1 (enabled)
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 863351c090d8..2f05f732d3fd 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -24,6 +24,7 @@
 static bool group0_trap;
 static bool group1_trap;
 static bool common_trap;
+static bool gicv4_enable;
 
 void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
 {
@@ -461,6 +462,12 @@ static int __init early_common_trap_cfg(char *buf)
 }
 early_param("kvm-arm.vgic_v3_common_trap", early_common_trap_cfg);
 
+static int __init early_gicv4_enable(char *buf)
+{
+	return strtobool(buf, &gicv4_enable);
+}
+early_param("kvm-arm.vgic_v4_enable", early_gicv4_enable);
+
 /**
  * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
  * @node:	pointer to the DT node
@@ -480,6 +487,13 @@ int vgic_v3_probe(const struct gic_kvm_info *info)
 	kvm_vgic_global_state.can_emulate_gicv2 = false;
 	kvm_vgic_global_state.ich_vtr_el2 = ich_vtr_el2;
 
+	/* GICv4 support? */
+	if (info->has_v4) {
+		kvm_vgic_global_state.has_gicv4 = gicv4_enable;
+		kvm_info("GICv4 support %sabled\n",
+			 gicv4_enable ? "en" : "dis");
+	}
+
 	if (!info->vcpu.start) {
 		kvm_info("GICv3: no GICV resource entry\n");
 		kvm_vgic_global_state.vcpu_base = 0;
-- 
2.14.2

[PULL 25/27] KVM: arm/arm64: GICv4: Theory of operations

[Christoffer Dall]

From: Marc Zyngier <marc.zyngier@arm.com>

Yet another braindump so I can free some cells...

Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-v4.c | 67 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 67 insertions(+)

diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index bf874dd01fc0..915d09dc2638 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -23,6 +23,73 @@
 
 #include "vgic.h"
 
+/*
+ * How KVM uses GICv4 (insert rude comments here):
+ *
+ * The vgic-v4 layer acts as a bridge between several entities:
+ * - The GICv4 ITS representation offered by the ITS driver
+ * - VFIO, which is in charge of the PCI endpoint
+ * - The virtual ITS, which is the only thing the guest sees
+ *
+ * The configuration of VLPIs is triggered by a callback from VFIO,
+ * instructing KVM that a PCI device has been configured to deliver
+ * MSIs to a vITS.
+ *
+ * kvm_vgic_v4_set_forwarding() is thus called with the routing entry,
+ * and this is used to find the corresponding vITS data structures
+ * (ITS instance, device, event and irq) using a process that is
+ * extremely similar to the injection of an MSI.
+ *
+ * At this stage, we can link the guest's view of an LPI (uniquely
+ * identified by the routing entry) and the host irq, using the GICv4
+ * driver mapping operation. Should the mapping succeed, we've then
+ * successfully upgraded the guest's LPI to a VLPI. We can then start
+ * with updating GICv4's view of the property table and generating an
+ * INValidation in order to kickstart the delivery of this VLPI to the
+ * guest directly, without software intervention. Well, almost.
+ *
+ * When the PCI endpoint is deconfigured, this operation is reversed
+ * with VFIO calling kvm_vgic_v4_unset_forwarding().
+ *
+ * Once the VLPI has been mapped, it needs to follow any change the
+ * guest performs on its LPI through the vITS. For that, a number of
+ * command handlers have hooks to communicate these changes to the HW:
+ * - Any invalidation triggers a call to its_prop_update_vlpi()
+ * - The INT command results in a irq_set_irqchip_state(), which
+ *   generates an INT on the corresponding VLPI.
+ * - The CLEAR command results in a irq_set_irqchip_state(), which
+ *   generates an CLEAR on the corresponding VLPI.
+ * - DISCARD translates into an unmap, similar to a call to
+ *   kvm_vgic_v4_unset_forwarding().
+ * - MOVI is translated by an update of the existing mapping, changing
+ *   the target vcpu, resulting in a VMOVI being generated.
+ * - MOVALL is translated by a string of mapping updates (similar to
+ *   the handling of MOVI). MOVALL is horrible.
+ *
+ * Note that a DISCARD/MAPTI sequence emitted from the guest without
+ * reprogramming the PCI endpoint after MAPTI does not result in a
+ * VLPI being mapped, as there is no callback from VFIO (the guest
+ * will get the interrupt via the normal SW injection). Fixing this is
+ * not trivial, and requires some horrible messing with the VFIO
+ * internals. Not fun. Don't do that.
+ *
+ * Then there is the scheduling. Each time a vcpu is about to run on a
+ * physical CPU, KVM must tell the corresponding redistributor about
+ * it. And if we've migrated our vcpu from one CPU to another, we must
+ * tell the ITS (so that the messages reach the right redistributor).
+ * This is done in two steps: first issue a irq_set_affinity() on the
+ * irq corresponding to the vcpu, then call its_schedule_vpe(). You
+ * must be in a non-preemptible context. On exit, another call to
+ * its_schedule_vpe() tells the redistributor that we're done with the
+ * vcpu.
+ *
+ * Finally, the doorbell handling: Each vcpu is allocated an interrupt
+ * which will fire each time a VLPI is made pending whilst the vcpu is
+ * not running. Each time the vcpu gets blocked, the doorbell
+ * interrupt gets enabled. When the vcpu is unblocked (for whatever
+ * reason), the doorbell interrupt is disabled.
+ */
+
 #define DB_IRQ_FLAGS	(IRQ_NOAUTOEN | IRQ_DISABLE_UNLAZY | IRQ_NO_BALANCING)
 
 static irqreturn_t vgic_v4_doorbell_handler(int irq, void *info)
-- 
2.14.2

[PULL 26/27] KVM: arm/arm64: Fix GICv4 ITS initialization issues

[Christoffer Dall]

We should only try to initialize GICv4 data structures on a GICv4
capable system.  Move the vgic_supports_direct_msis() check inito
vgic_v4_init() so that any KVM VGIC initialization path does not fail
on non-GICv4 systems.

Also be slightly more strict in the checking of the return value in
vgic_its_create, and only error out on negative return values from the
vgic_v4_init() function.  This is important because the kvm device code
only treats negative values as errors and only cleans up in this case.
Errornously treating a positive return value as an error from the
vgic_v4_init() function can lead to NULL pointer dereferences, as has
recently been observed.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-init.c | 8 +++-----
 virt/kvm/arm/vgic/vgic-its.c  | 2 +-
 virt/kvm/arm/vgic/vgic-v4.c   | 3 +++
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 40be908da238..62310122ee78 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -285,11 +285,9 @@ int vgic_init(struct kvm *kvm)
 	if (ret)
 		goto out;
 
-	if (vgic_supports_direct_msis(kvm)) {
-		ret = vgic_v4_init(kvm);
-		if (ret)
-			goto out;
-	}
+	ret = vgic_v4_init(kvm);
+	if (ret)
+		goto out;
 
 	kvm_for_each_vcpu(i, vcpu, kvm)
 		kvm_vgic_vcpu_enable(vcpu);
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index b8c1b724ba3e..c93ecd4a903b 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -1673,7 +1673,7 @@ static int vgic_its_create(struct kvm_device *dev, u32 type)
 
 	if (vgic_initialized(dev->kvm)) {
 		int ret = vgic_v4_init(dev->kvm);
-		if (ret) {
+		if (ret < 0) {
 			kfree(its);
 			return ret;
 		}
diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c
index 915d09dc2638..53c324aa44ef 100644
--- a/virt/kvm/arm/vgic/vgic-v4.c
+++ b/virt/kvm/arm/vgic/vgic-v4.c
@@ -118,6 +118,9 @@ int vgic_v4_init(struct kvm *kvm)
 	struct kvm_vcpu *vcpu;
 	int i, nr_vcpus, ret;
 
+	if (!vgic_supports_direct_msis(kvm))
+		return 0; /* Nothing to see here... move along. */
+
 	if (dist->its_vm.vpes)
 		return 0;
 
-- 
2.14.2

[PULL 27/27] KVM: arm/arm64: Don't queue VLPIs on INV/INVALL

[Christoffer Dall]

Since VLPIs are injected directly by the hardware there's no need to
mark these as pending in software and queue them on the AP list.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 virt/kvm/arm/vgic/vgic-its.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index c93ecd4a903b..a3754ec719c4 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -292,11 +292,14 @@ static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
 		irq->priority = LPI_PROP_PRIORITY(prop);
 		irq->enabled = LPI_PROP_ENABLE_BIT(prop);
 
-		vgic_queue_irq_unlock(kvm, irq, flags);
-	} else {
-		spin_unlock_irqrestore(&irq->irq_lock, flags);
+		if (!irq->hw) {
+			vgic_queue_irq_unlock(kvm, irq, flags);
+			return 0;
+		}
 	}
 
+	spin_unlock_irqrestore(&irq->irq_lock, flags);
+
 	if (irq->hw)
 		return its_prop_update_vlpi(irq->host_irq, prop, needs_inv);
 
-- 
2.14.2

[PULL 00/27] KVM/ARM GICv4 Support for v4.15

[Paolo Bonzini]

On 13/11/2017 10:17, Christoffer Dall wrote:
>   git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm.git tags/kvm-arm-gicv4-for-v4.15

Pulled, thanks.

Paolo