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-rw-r--r--Documentation/virt/kvm/devices/arm-vgic-its.rst2
-rw-r--r--arch/arm64/kvm/vgic/vgic-its.c6
-rw-r--r--arch/arm64/kvm/vgic/vgic-v3.c66
-rw-r--r--arch/arm64/kvm/vgic/vgic-v4.c38
-rw-r--r--arch/arm64/kvm/vgic/vgic.h1
-rw-r--r--drivers/irqchip/irq-gic-v3-its.c18
6 files changed, 119 insertions, 12 deletions
diff --git a/Documentation/virt/kvm/devices/arm-vgic-its.rst b/Documentation/virt/kvm/devices/arm-vgic-its.rst
index 6c304fd2b1b4..d257eddbae29 100644
--- a/Documentation/virt/kvm/devices/arm-vgic-its.rst
+++ b/Documentation/virt/kvm/devices/arm-vgic-its.rst
@@ -80,7 +80,7 @@ KVM_DEV_ARM_VGIC_GRP_CTRL
-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
+ state is not available without GICv4.1
======= ==========================================================
KVM_DEV_ARM_VGIC_GRP_ITS_REGS
diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c
index 40cbaca81333..ec7543a9617c 100644
--- a/arch/arm64/kvm/vgic/vgic-its.c
+++ b/arch/arm64/kvm/vgic/vgic-its.c
@@ -2218,10 +2218,10 @@ static int vgic_its_save_itt(struct vgic_its *its, struct its_device *device)
/*
* 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...
+ * have direct access to that state without GICv4.1.
+ * Let's simply fail the save operation...
*/
- if (ite->irq->hw)
+ if (ite->irq->hw && !kvm_vgic_global_state.has_gicv4_1)
return -EACCES;
ret = vgic_its_save_ite(its, device, ite, gpa, ite_esz);
diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c
index 6f530925a231..41ecf219c333 100644
--- a/arch/arm64/kvm/vgic/vgic-v3.c
+++ b/arch/arm64/kvm/vgic/vgic-v3.c
@@ -1,6 +1,8 @@
// SPDX-License-Identifier: GPL-2.0-only
#include <linux/irqchip/arm-gic-v3.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <kvm/arm_vgic.h>
@@ -356,6 +358,32 @@ retry:
return 0;
}
+/*
+ * The deactivation of the doorbell interrupt will trigger the
+ * unmapping of the associated vPE.
+ */
+static void unmap_all_vpes(struct vgic_dist *dist)
+{
+ struct irq_desc *desc;
+ int i;
+
+ for (i = 0; i < dist->its_vm.nr_vpes; i++) {
+ desc = irq_to_desc(dist->its_vm.vpes[i]->irq);
+ irq_domain_deactivate_irq(irq_desc_get_irq_data(desc));
+ }
+}
+
+static void map_all_vpes(struct vgic_dist *dist)
+{
+ struct irq_desc *desc;
+ int i;
+
+ for (i = 0; i < dist->its_vm.nr_vpes; i++) {
+ desc = irq_to_desc(dist->its_vm.vpes[i]->irq);
+ irq_domain_activate_irq(irq_desc_get_irq_data(desc), false);
+ }
+}
+
/**
* vgic_v3_save_pending_tables - Save the pending tables into guest RAM
* kvm lock and all vcpu lock must be held
@@ -365,13 +393,28 @@ int vgic_v3_save_pending_tables(struct kvm *kvm)
struct vgic_dist *dist = &kvm->arch.vgic;
struct vgic_irq *irq;
gpa_t last_ptr = ~(gpa_t)0;
- int ret;
+ bool vlpi_avail = false;
+ int ret = 0;
u8 val;
+ if (unlikely(!vgic_initialized(kvm)))
+ return -ENXIO;
+
+ /*
+ * A preparation for getting any VLPI states.
+ * The above vgic initialized check also ensures that the allocation
+ * and enabling of the doorbells have already been done.
+ */
+ if (kvm_vgic_global_state.has_gicv4_1) {
+ unmap_all_vpes(dist);
+ vlpi_avail = true;
+ }
+
list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
int byte_offset, bit_nr;
struct kvm_vcpu *vcpu;
gpa_t pendbase, ptr;
+ bool is_pending;
bool stored;
vcpu = irq->target_vcpu;
@@ -387,24 +430,35 @@ int vgic_v3_save_pending_tables(struct kvm *kvm)
if (ptr != last_ptr) {
ret = kvm_read_guest_lock(kvm, ptr, &val, 1);
if (ret)
- return ret;
+ goto out;
last_ptr = ptr;
}
stored = val & (1U << bit_nr);
- if (stored == irq->pending_latch)
+
+ is_pending = irq->pending_latch;
+
+ if (irq->hw && vlpi_avail)
+ vgic_v4_get_vlpi_state(irq, &is_pending);
+
+ if (stored == is_pending)
continue;
- if (irq->pending_latch)
+ if (is_pending)
val |= 1 << bit_nr;
else
val &= ~(1 << bit_nr);
ret = kvm_write_guest_lock(kvm, ptr, &val, 1);
if (ret)
- return ret;
+ goto out;
}
- return 0;
+
+out:
+ if (vlpi_avail)
+ map_all_vpes(dist);
+
+ return ret;
}
/**
diff --git a/arch/arm64/kvm/vgic/vgic-v4.c b/arch/arm64/kvm/vgic/vgic-v4.c
index 66508b03094f..c1845d8f5f7e 100644
--- a/arch/arm64/kvm/vgic/vgic-v4.c
+++ b/arch/arm64/kvm/vgic/vgic-v4.c
@@ -203,6 +203,25 @@ void vgic_v4_configure_vsgis(struct kvm *kvm)
kvm_arm_resume_guest(kvm);
}
+/*
+ * Must be called with GICv4.1 and the vPE unmapped, which
+ * indicates the invalidation of any VPT caches associated
+ * with the vPE, thus we can get the VLPI state by peeking
+ * at the VPT.
+ */
+void vgic_v4_get_vlpi_state(struct vgic_irq *irq, bool *val)
+{
+ struct its_vpe *vpe = &irq->target_vcpu->arch.vgic_cpu.vgic_v3.its_vpe;
+ int mask = BIT(irq->intid % BITS_PER_BYTE);
+ void *va;
+ u8 *ptr;
+
+ va = page_address(vpe->vpt_page);
+ ptr = va + irq->intid / BITS_PER_BYTE;
+
+ *val = !!(*ptr & mask);
+}
+
/**
* vgic_v4_init - Initialize the GICv4 data structures
* @kvm: Pointer to the VM being initialized
@@ -385,6 +404,7 @@ int kvm_vgic_v4_set_forwarding(struct kvm *kvm, int virq,
struct vgic_its *its;
struct vgic_irq *irq;
struct its_vlpi_map map;
+ unsigned long flags;
int ret;
if (!vgic_supports_direct_msis(kvm))
@@ -430,6 +450,24 @@ int kvm_vgic_v4_set_forwarding(struct kvm *kvm, int virq,
irq->host_irq = virq;
atomic_inc(&map.vpe->vlpi_count);
+ /* Transfer pending state */
+ raw_spin_lock_irqsave(&irq->irq_lock, flags);
+ if (irq->pending_latch) {
+ ret = irq_set_irqchip_state(irq->host_irq,
+ IRQCHIP_STATE_PENDING,
+ irq->pending_latch);
+ WARN_RATELIMIT(ret, "IRQ %d", irq->host_irq);
+
+ /*
+ * Clear pending_latch and communicate this state
+ * change via vgic_queue_irq_unlock.
+ */
+ irq->pending_latch = false;
+ vgic_queue_irq_unlock(kvm, irq, flags);
+ } else {
+ raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
+ }
+
out:
mutex_unlock(&its->its_lock);
return ret;
diff --git a/arch/arm64/kvm/vgic/vgic.h b/arch/arm64/kvm/vgic/vgic.h
index bc418c2c1214..dc1f3d1657ee 100644
--- a/arch/arm64/kvm/vgic/vgic.h
+++ b/arch/arm64/kvm/vgic/vgic.h
@@ -318,5 +318,6 @@ bool vgic_supports_direct_msis(struct kvm *kvm);
int vgic_v4_init(struct kvm *kvm);
void vgic_v4_teardown(struct kvm *kvm);
void vgic_v4_configure_vsgis(struct kvm *kvm);
+void vgic_v4_get_vlpi_state(struct vgic_irq *irq, bool *val);
#endif
diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index ed46e6057e33..d205fafede37 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -794,8 +794,13 @@ static struct its_vpe *its_build_vmapp_cmd(struct its_node *its,
its_encode_alloc(cmd, alloc);
- /* We can only signal PTZ when alloc==1. Why do we have two bits? */
- its_encode_ptz(cmd, alloc);
+ /*
+ * GICv4.1 provides a way to get the VLPI state, which needs the vPE
+ * to be unmapped first, and in this case, we may remap the vPE
+ * back while the VPT is not empty. So we can't assume that the
+ * VPT is empty on map. This is why we never advertise PTZ.
+ */
+ its_encode_ptz(cmd, false);
its_encode_vconf_addr(cmd, vconf_addr);
its_encode_vmapp_default_db(cmd, desc->its_vmapp_cmd.vpe->vpe_db_lpi);
@@ -4554,6 +4559,15 @@ static void its_vpe_irq_domain_deactivate(struct irq_domain *domain,
its_send_vmapp(its, vpe, false);
}
+
+ /*
+ * There may be a direct read to the VPT after unmapping the
+ * vPE, to guarantee the validity of this, we make the VPT
+ * memory coherent with the CPU caches here.
+ */
+ if (find_4_1_its() && !atomic_read(&vpe->vmapp_count))
+ gic_flush_dcache_to_poc(page_address(vpe->vpt_page),
+ LPI_PENDBASE_SZ);
}
static const struct irq_domain_ops its_vpe_domain_ops = {