Merge branch 'kvm-arm64/gic-v4.1' into kvmarm-master/next

Signed-off-by: NMarc Zyngier <maz@kernel.org>

arch/arm/include/asm/kvm_host.h

@@ -39,6 +39,7 @@
 #define KVM_REQ_IRQ_PENDING	KVM_ARCH_REQ(1)
 #define KVM_REQ_VCPU_RESET	KVM_ARCH_REQ(2)
 #define KVM_REQ_RECORD_STEAL	KVM_ARCH_REQ(3)
+#define KVM_REQ_RELOAD_GICv4	KVM_ARCH_REQ(4)
 
 DECLARE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
 

arch/arm64/include/asm/kvm_emulate.h

@@ -89,7 +89,8 @@ static inline unsigned long *vcpu_hcr(struct kvm_vcpu *vcpu)
 static inline void vcpu_clear_wfx_traps(struct kvm_vcpu *vcpu)
 {
 	vcpu->arch.hcr_el2 &= ~HCR_TWE;
-	if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count))
+	if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
+	    vcpu->kvm->arch.vgic.nassgireq)
 		vcpu->arch.hcr_el2 &= ~HCR_TWI;
 	else
 		vcpu->arch.hcr_el2 |= HCR_TWI;

arch/arm64/include/asm/kvm_host.h

@@ -44,6 +44,7 @@
 #define KVM_REQ_IRQ_PENDING	KVM_ARCH_REQ(1)
 #define KVM_REQ_VCPU_RESET	KVM_ARCH_REQ(2)
 #define KVM_REQ_RECORD_STEAL	KVM_ARCH_REQ(3)
+#define KVM_REQ_RELOAD_GICv4	KVM_ARCH_REQ(4)
 
 DECLARE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
 

drivers/irqchip/irq-gic-v3-its.c

@@ -96,6 +96,7 @@ struct its_node {
 	struct mutex		dev_alloc_lock;
 	struct list_head	entry;
 	void __iomem		*base;
+	void __iomem		*sgir_base;
 	phys_addr_t		phys_base;
 	struct its_cmd_block	*cmd_base;
 	struct its_cmd_block	*cmd_write;
@@ -188,6 +189,15 @@ static DEFINE_IDA(its_vpeid_ida);
 #define gic_data_rdist_rd_base()	(gic_data_rdist()->rd_base)
 #define gic_data_rdist_vlpi_base()	(gic_data_rdist_rd_base() + SZ_128K)
 
+/*
+ * Skip ITSs that have no vLPIs mapped, unless we're on GICv4.1, as we
+ * always have vSGIs mapped.
+ */
+static bool require_its_list_vmovp(struct its_vm *vm, struct its_node *its)
+{
+	return (gic_rdists->has_rvpeid || vm->vlpi_count[its->list_nr]);
+}
+
 static u16 get_its_list(struct its_vm *vm)
 {
 	struct its_node *its;
@@ -197,7 +207,7 @@ static u16 get_its_list(struct its_vm *vm)
 		if (!is_v4(its))
 			continue;
 
-		if (vm->vlpi_count[its->list_nr])
+		if (require_its_list_vmovp(vm, its))
 			__set_bit(its->list_nr, &its_list);
 	}
 
@@ -239,15 +249,41 @@ static struct its_vlpi_map *get_vlpi_map(struct irq_data *d)
 	return NULL;
 }
 
-static int irq_to_cpuid(struct irq_data *d)
+static int vpe_to_cpuid_lock(struct its_vpe *vpe, unsigned long *flags)
+{
+	raw_spin_lock_irqsave(&vpe->vpe_lock, *flags);
+	return vpe->col_idx;
+}
+
+static void vpe_to_cpuid_unlock(struct its_vpe *vpe, unsigned long flags)
+{
+	raw_spin_unlock_irqrestore(&vpe->vpe_lock, flags);
+}
+
+static int irq_to_cpuid_lock(struct irq_data *d, unsigned long *flags)
+{
+	struct its_vlpi_map *map = get_vlpi_map(d);
+	int cpu;
+
+	if (map) {
+		cpu = vpe_to_cpuid_lock(map->vpe, flags);
+	} else {
+		/* Physical LPIs are already locked via the irq_desc lock */
+		struct its_device *its_dev = irq_data_get_irq_chip_data(d);
+		cpu = its_dev->event_map.col_map[its_get_event_id(d)];
+		/* Keep GCC quiet... */
+		*flags = 0;
+	}
+
+	return cpu;
+}
+
+static void irq_to_cpuid_unlock(struct irq_data *d, unsigned long flags)
 {
-	struct its_device *its_dev = irq_data_get_irq_chip_data(d);
 	struct its_vlpi_map *map = get_vlpi_map(d);
 
 	if (map)
-		return map->vpe->col_idx;
-
-	return its_dev->event_map.col_map[its_get_event_id(d)];
+		vpe_to_cpuid_unlock(map->vpe, flags);
 }
 
 static struct its_collection *valid_col(struct its_collection *col)
@@ -353,6 +389,15 @@ struct its_cmd_desc {
 		struct {
 			struct its_vpe *vpe;
 		} its_invdb_cmd;
+
+		struct {
+			struct its_vpe *vpe;
+			u8 sgi;
+			u8 priority;
+			bool enable;
+			bool group;
+			bool clear;
+		} its_vsgi_cmd;
 	};
 };
 
@@ -501,6 +546,31 @@ static void its_encode_db(struct its_cmd_block *cmd, bool db)
 	its_mask_encode(&cmd->raw_cmd[2], db, 63, 63);
 }
 
+static void its_encode_sgi_intid(struct its_cmd_block *cmd, u8 sgi)
+{
+	its_mask_encode(&cmd->raw_cmd[0], sgi, 35, 32);
+}
+
+static void its_encode_sgi_priority(struct its_cmd_block *cmd, u8 prio)
+{
+	its_mask_encode(&cmd->raw_cmd[0], prio >> 4, 23, 20);
+}
+
+static void its_encode_sgi_group(struct its_cmd_block *cmd, bool grp)
+{
+	its_mask_encode(&cmd->raw_cmd[0], grp, 10, 10);
+}
+
+static void its_encode_sgi_clear(struct its_cmd_block *cmd, bool clr)
+{
+	its_mask_encode(&cmd->raw_cmd[0], clr, 9, 9);
+}
+
+static void its_encode_sgi_enable(struct its_cmd_block *cmd, bool en)
+{
+	its_mask_encode(&cmd->raw_cmd[0], en, 8, 8);
+}
+
 static inline void its_fixup_cmd(struct its_cmd_block *cmd)
 {
 	/* Let's fixup BE commands */
@@ -866,6 +936,26 @@ static struct its_vpe *its_build_invdb_cmd(struct its_node *its,
 	return valid_vpe(its, desc->its_invdb_cmd.vpe);
 }
 
+static struct its_vpe *its_build_vsgi_cmd(struct its_node *its,
+					  struct its_cmd_block *cmd,
+					  struct its_cmd_desc *desc)
+{
+	if (WARN_ON(!is_v4_1(its)))
+		return NULL;
+
+	its_encode_cmd(cmd, GITS_CMD_VSGI);
+	its_encode_vpeid(cmd, desc->its_vsgi_cmd.vpe->vpe_id);
+	its_encode_sgi_intid(cmd, desc->its_vsgi_cmd.sgi);
+	its_encode_sgi_priority(cmd, desc->its_vsgi_cmd.priority);
+	its_encode_sgi_group(cmd, desc->its_vsgi_cmd.group);
+	its_encode_sgi_clear(cmd, desc->its_vsgi_cmd.clear);
+	its_encode_sgi_enable(cmd, desc->its_vsgi_cmd.enable);
+
+	its_fixup_cmd(cmd);
+
+	return valid_vpe(its, desc->its_vsgi_cmd.vpe);
+}
+
 static u64 its_cmd_ptr_to_offset(struct its_node *its,
 				 struct its_cmd_block *ptr)
 {
@@ -1214,7 +1304,7 @@ static void its_send_vmovp(struct its_vpe *vpe)
 		if (!is_v4(its))
 			continue;
 
-		if (!vpe->its_vm->vlpi_count[its->list_nr])
+		if (!require_its_list_vmovp(vpe->its_vm, its))
 			continue;
 
 		desc.its_vmovp_cmd.col = &its->collections[col_id];
@@ -1329,7 +1419,9 @@ static void direct_lpi_inv(struct irq_data *d)
 {
 	struct its_vlpi_map *map = get_vlpi_map(d);
 	void __iomem *rdbase;
+	unsigned long flags;
 	u64 val;
+	int cpu;
 
 	if (map) {
 		struct its_device *its_dev = irq_data_get_irq_chip_data(d);
@@ -1344,10 +1436,14 @@ static void direct_lpi_inv(struct irq_data *d)
 	}
 
 	/* Target the redistributor this LPI is currently routed to */
-	rdbase = per_cpu_ptr(gic_rdists->rdist, irq_to_cpuid(d))->rd_base;
+	cpu = irq_to_cpuid_lock(d, &flags);
+	raw_spin_lock(&gic_data_rdist_cpu(cpu)->rd_lock);
+	rdbase = per_cpu_ptr(gic_rdists->rdist, cpu)->rd_base;
 	gic_write_lpir(val, rdbase + GICR_INVLPIR);
 
 	wait_for_syncr(rdbase);
+	raw_spin_unlock(&gic_data_rdist_cpu(cpu)->rd_lock);
+	irq_to_cpuid_unlock(d, flags);
 }
 
 static void lpi_update_config(struct irq_data *d, u8 clr, u8 set)
@@ -1499,12 +1595,31 @@ static int its_irq_set_irqchip_state(struct irq_data *d,
 	return 0;
 }
 
+/*
+ * Two favourable cases:
+ *
+ * (a) Either we have a GICv4.1, and all vPEs have to be mapped at all times
+ *     for vSGI delivery
+ *
+ * (b) Or the ITSs do not use a list map, meaning that VMOVP is cheap enough
+ *     and we're better off mapping all VPEs always
+ *
+ * If neither (a) nor (b) is true, then we map vPEs on demand.
+ *
+ */
+static bool gic_requires_eager_mapping(void)
+{
+	if (!its_list_map || gic_rdists->has_rvpeid)
+		return true;
+
+	return false;
+}
+
 static void its_map_vm(struct its_node *its, struct its_vm *vm)
 {
 	unsigned long flags;
 
-	/* Not using the ITS list? Everything is always mapped. */
-	if (!its_list_map)
+	if (gic_requires_eager_mapping())
 		return;
 
 	raw_spin_lock_irqsave(&vmovp_lock, flags);
@@ -1538,7 +1653,7 @@ static void its_unmap_vm(struct its_node *its, struct its_vm *vm)
 	unsigned long flags;
 
 	/* Not using the ITS list? Everything is always mapped. */
-	if (!its_list_map)
+	if (gic_requires_eager_mapping())
 		return;
 
 	raw_spin_lock_irqsave(&vmovp_lock, flags);
@@ -2452,6 +2567,10 @@ static bool allocate_vpe_l2_table(int cpu, u32 id)
 	if (!gic_rdists->has_rvpeid)
 		return true;
 
+	/* Skip non-present CPUs */
+	if (!base)
+		return true;
+
 	val  = gicr_read_vpropbaser(base + SZ_128K + GICR_VPROPBASER);
 
 	esz  = FIELD_GET(GICR_VPROPBASER_4_1_ENTRY_SIZE, val) + 1;
@@ -3482,17 +3601,25 @@ static int its_vpe_set_affinity(struct irq_data *d,
 {
 	struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
 	int from, cpu = cpumask_first(mask_val);
+	unsigned long flags;
 
 	/*
 	 * Changing affinity is mega expensive, so let's be as lazy as
 	 * we can and only do it if we really have to. Also, if mapped
 	 * into the proxy device, we need to move the doorbell
 	 * interrupt to its new location.
+	 *
+	 * Another thing is that changing the affinity of a vPE affects
+	 * *other interrupts* such as all the vLPIs that are routed to
+	 * this vPE. This means that the irq_desc lock is not enough to
+	 * protect us, and that we must ensure nobody samples vpe->col_idx
+	 * during the update, hence the lock below which must also be
+	 * taken on any vLPI handling path that evaluates vpe->col_idx.
 	 */
-	if (vpe->col_idx == cpu)
+	from = vpe_to_cpuid_lock(vpe, &flags);
+	if (from == cpu)
 		goto out;
 
-	from = vpe->col_idx;
 	vpe->col_idx = cpu;
 
 	/*
@@ -3508,6 +3635,7 @@ static int its_vpe_set_affinity(struct irq_data *d,
 
 out:
 	irq_data_update_effective_affinity(d, cpumask_of(cpu));
+	vpe_to_cpuid_unlock(vpe, flags);
 
 	return IRQ_SET_MASK_OK_DONE;
 }
@@ -3619,9 +3747,11 @@ static void its_vpe_send_inv(struct irq_data *d)
 		void __iomem *rdbase;
 
 		/* Target the redistributor this VPE is currently known on */
+		raw_spin_lock(&gic_data_rdist_cpu(vpe->col_idx)->rd_lock);
 		rdbase = per_cpu_ptr(gic_rdists->rdist, vpe->col_idx)->rd_base;
 		gic_write_lpir(d->parent_data->hwirq, rdbase + GICR_INVLPIR);
 		wait_for_syncr(rdbase);
+		raw_spin_unlock(&gic_data_rdist_cpu(vpe->col_idx)->rd_lock);
 	} else {
 		its_vpe_send_cmd(vpe, its_send_inv);
 	}
@@ -3782,8 +3912,12 @@ static void its_vpe_4_1_invall(struct its_vpe *vpe)
 	val |= FIELD_PREP(GICR_INVALLR_VPEID, vpe->vpe_id);
 
 	/* Target the redistributor this vPE is currently known on */
+	raw_spin_lock(&gic_data_rdist_cpu(vpe->col_idx)->rd_lock);
 	rdbase = per_cpu_ptr(gic_rdists->rdist, vpe->col_idx)->rd_base;
 	gic_write_lpir(val, rdbase + GICR_INVALLR);
+
+	wait_for_syncr(rdbase);
+	raw_spin_unlock(&gic_data_rdist_cpu(vpe->col_idx)->rd_lock);
 }
 
 static int its_vpe_4_1_set_vcpu_affinity(struct irq_data *d, void *vcpu_info)
@@ -3818,6 +3952,221 @@ static struct irq_chip its_vpe_4_1_irq_chip = {
 	.irq_set_vcpu_affinity	= its_vpe_4_1_set_vcpu_affinity,
 };
 
+static void its_configure_sgi(struct irq_data *d, bool clear)
+{
+	struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
+	struct its_cmd_desc desc;
+
+	desc.its_vsgi_cmd.vpe = vpe;
+	desc.its_vsgi_cmd.sgi = d->hwirq;
+	desc.its_vsgi_cmd.priority = vpe->sgi_config[d->hwirq].priority;
+	desc.its_vsgi_cmd.enable = vpe->sgi_config[d->hwirq].enabled;
+	desc.its_vsgi_cmd.group = vpe->sgi_config[d->hwirq].group;
+	desc.its_vsgi_cmd.clear = clear;
+
+	/*
+	 * GICv4.1 allows us to send VSGI commands to any ITS as long as the
+	 * destination VPE is mapped there. Since we map them eagerly at
+	 * activation time, we're pretty sure the first GICv4.1 ITS will do.
+	 */
+	its_send_single_vcommand(find_4_1_its(), its_build_vsgi_cmd, &desc);
+}
+
+static void its_sgi_mask_irq(struct irq_data *d)
+{
+	struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
+
+	vpe->sgi_config[d->hwirq].enabled = false;
+	its_configure_sgi(d, false);
+}
+
+static void its_sgi_unmask_irq(struct irq_data *d)
+{
+	struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
+
+	vpe->sgi_config[d->hwirq].enabled = true;
+	its_configure_sgi(d, false);
+}
+
+static int its_sgi_set_affinity(struct irq_data *d,
+				const struct cpumask *mask_val,
+				bool force)
+{
+	/*
+	 * There is no notion of affinity for virtual SGIs, at least
+	 * not on the host (since they can only be targetting a vPE).
+	 * Tell the kernel we've done whatever it asked for.
+	 */
+	return IRQ_SET_MASK_OK;
+}
+
+static int its_sgi_set_irqchip_state(struct irq_data *d,
+				     enum irqchip_irq_state which,
+				     bool state)
+{
+	if (which != IRQCHIP_STATE_PENDING)
+		return -EINVAL;
+
+	if (state) {
+		struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
+		struct its_node *its = find_4_1_its();
+		u64 val;
+
+		val  = FIELD_PREP(GITS_SGIR_VPEID, vpe->vpe_id);
+		val |= FIELD_PREP(GITS_SGIR_VINTID, d->hwirq);
+		writeq_relaxed(val, its->sgir_base + GITS_SGIR - SZ_128K);
+	} else {
+		its_configure_sgi(d, true);
+	}
+
+	return 0;
+}
+
+static int its_sgi_get_irqchip_state(struct irq_data *d,
+				     enum irqchip_irq_state which, bool *val)
+{
+	struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
+	void __iomem *base;
+	unsigned long flags;
+	u32 count = 1000000;	/* 1s! */
+	u32 status;
+	int cpu;
+
+	if (which != IRQCHIP_STATE_PENDING)
+		return -EINVAL;
+
+	/*
+	 * Locking galore! We can race against two different events:
+	 *
+	 * - Concurent vPE affinity change: we must make sure it cannot
+	 *   happen, or we'll talk to the wrong redistributor. This is
+	 *   identical to what happens with vLPIs.
+	 *
+	 * - Concurrent VSGIPENDR access: As it involves accessing two
+	 *   MMIO registers, this must be made atomic one way or another.
+	 */
+	cpu = vpe_to_cpuid_lock(vpe, &flags);
+	raw_spin_lock(&gic_data_rdist_cpu(cpu)->rd_lock);
+	base = gic_data_rdist_cpu(cpu)->rd_base + SZ_128K;
+	writel_relaxed(vpe->vpe_id, base + GICR_VSGIR);
+	do {
+		status = readl_relaxed(base + GICR_VSGIPENDR);
+		if (!(status & GICR_VSGIPENDR_BUSY))
+			goto out;
+
+		count--;
+		if (!count) {
+			pr_err_ratelimited("Unable to get SGI status\n");
+			goto out;
+		}
+		cpu_relax();
+		udelay(1);
+	} while (count);
+
+out:
+	raw_spin_unlock(&gic_data_rdist_cpu(cpu)->rd_lock);
+	vpe_to_cpuid_unlock(vpe, flags);
+
+	if (!count)
+		return -ENXIO;
+
+	*val = !!(status & (1 << d->hwirq));
+
+	return 0;
+}
+
+static int its_sgi_set_vcpu_affinity(struct irq_data *d, void *vcpu_info)
+{
+	struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
+	struct its_cmd_info *info = vcpu_info;
+
+	switch (info->cmd_type) {
+	case PROP_UPDATE_VSGI:
+		vpe->sgi_config[d->hwirq].priority = info->priority;
+		vpe->sgi_config[d->hwirq].group = info->group;
+		its_configure_sgi(d, false);
+		return 0;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static struct irq_chip its_sgi_irq_chip = {
+	.name			= "GICv4.1-sgi",
+	.irq_mask		= its_sgi_mask_irq,
+	.irq_unmask		= its_sgi_unmask_irq,
+	.irq_set_affinity	= its_sgi_set_affinity,
+	.irq_set_irqchip_state	= its_sgi_set_irqchip_state,
+	.irq_get_irqchip_state	= its_sgi_get_irqchip_state,
+	.irq_set_vcpu_affinity	= its_sgi_set_vcpu_affinity,
+};
+
+static int its_sgi_irq_domain_alloc(struct irq_domain *domain,
+				    unsigned int virq, unsigned int nr_irqs,
+				    void *args)
+{
+	struct its_vpe *vpe = args;
+	int i;
+
+	/* Yes, we do want 16 SGIs */
+	WARN_ON(nr_irqs != 16);
+
+	for (i = 0; i < 16; i++) {
+		vpe->sgi_config[i].priority = 0;
+		vpe->sgi_config[i].enabled = false;
+		vpe->sgi_config[i].group = false;
+
+		irq_domain_set_hwirq_and_chip(domain, virq + i, i,
+					      &its_sgi_irq_chip, vpe);
+		irq_set_status_flags(virq + i, IRQ_DISABLE_UNLAZY);
+	}
+
+	return 0;
+}
+
+static void its_sgi_irq_domain_free(struct irq_domain *domain,
+				    unsigned int virq,
+				    unsigned int nr_irqs)
+{
+	/* Nothing to do */
+}
+
+static int its_sgi_irq_domain_activate(struct irq_domain *domain,
+				       struct irq_data *d, bool reserve)
+{
+	/* Write out the initial SGI configuration */
+	its_configure_sgi(d, false);
+	return 0;
+}
+
+static void its_sgi_irq_domain_deactivate(struct irq_domain *domain,
+					  struct irq_data *d)
+{
+	struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
+
+	/*
+	 * The VSGI command is awkward:
+	 *
+	 * - To change the configuration, CLEAR must be set to false,
+	 *   leaving the pending bit unchanged.
+	 * - To clear the pending bit, CLEAR must be set to true, leaving
+	 *   the configuration unchanged.
+	 *
+	 * You just can't do both at once, hence the two commands below.
+	 */
+	vpe->sgi_config[d->hwirq].enabled = false;
+	its_configure_sgi(d, false);
+	its_configure_sgi(d, true);
+}
+
+static const struct irq_domain_ops its_sgi_domain_ops = {
+	.alloc		= its_sgi_irq_domain_alloc,
+	.free		= its_sgi_irq_domain_free,
+	.activate	= its_sgi_irq_domain_activate,
+	.deactivate	= its_sgi_irq_domain_deactivate,
+};
+
 static int its_vpe_id_alloc(void)
 {
 	return ida_simple_get(&its_vpeid_ida, 0, ITS_MAX_VPEID, GFP_KERNEL);
@@ -3851,6 +4200,7 @@ static int its_vpe_init(struct its_vpe *vpe)
 		return -ENOMEM;
 	}
 
+	raw_spin_lock_init(&vpe->vpe_lock);
 	vpe->vpe_id = vpe_id;
 	vpe->vpt_page = vpt_page;
 	if (gic_rdists->has_rvpeid)
@@ -3960,8 +4310,12 @@ static int its_vpe_irq_domain_activate(struct irq_domain *domain,
 	struct its_vpe *vpe = irq_data_get_irq_chip_data(d);
 	struct its_node *its;
 
-	/* If we use the list map, we issue VMAPP on demand... */
-	if (its_list_map)
+	/*
+	 * If we use the list map, we issue VMAPP on demand... Unless
+	 * we're on a GICv4.1 and we eagerly map the VPE on all ITSs
+	 * so that VSGIs can work.
+	 */
+	if (!gic_requires_eager_mapping())
 		return 0;
 
 	/* Map the VPE to the first possible CPU */
@@ -3987,10 +4341,10 @@ static void its_vpe_irq_domain_deactivate(struct irq_domain *domain,
 	struct its_node *its;
 
 	/*
-	 * If we use the list map, we unmap the VPE once no VLPIs are
-	 * associated with the VM.
+	 * If we use the list map on GICv4.0, we unmap the VPE once no
+	 * VLPIs are associated with the VM.
 	 */
-	if (its_list_map)
+	if (!gic_requires_eager_mapping())
 		return;
 
 	list_for_each_entry(its, &its_nodes, entry) {
@@ -4404,7 +4758,7 @@ static int __init its_probe_one(struct resource *res,
 	struct page *page;
 	int err;
 
-	its_base = ioremap(res->start, resource_size(res));
+	its_base = ioremap(res->start, SZ_64K);
 	if (!its_base) {
 		pr_warn("ITS@%pa: Unable to map ITS registers\n", &res->start);
 		return -ENOMEM;
@@ -4455,6 +4809,13 @@ static int __init its_probe_one(struct resource *res,
 
 		if (is_v4_1(its)) {
 			u32 svpet = FIELD_GET(GITS_TYPER_SVPET, typer);
+
+			its->sgir_base = ioremap(res->start + SZ_128K, SZ_64K);
+			if (!its->sgir_base) {
+				err = -ENOMEM;
+				goto out_free_its;
+			}
+
 			its->mpidr = readl_relaxed(its_base + GITS_MPIDR);
 
 			pr_info("ITS@%pa: Using GICv4.1 mode %08x %08x\n",
@@ -4468,7 +4829,7 @@ static int __init its_probe_one(struct resource *res,
 				get_order(ITS_CMD_QUEUE_SZ));
 	if (!page) {
 		err = -ENOMEM;
-		goto out_free_its;
+		goto out_unmap_sgir;
 	}
 	its->cmd_base = (void *)page_address(page);
 	its->cmd_write = its->cmd_base;
@@ -4535,6 +4896,9 @@ static int __init its_probe_one(struct resource *res,
 	its_free_tables(its);
 out_free_cmd:
 	free_pages((unsigned long)its->cmd_base, get_order(ITS_CMD_QUEUE_SZ));
+out_unmap_sgir:
+	if (its->sgir_base)
+		iounmap(its->sgir_base);
 out_free_its:
 	kfree(its);
 out_unmap:
@@ -4818,6 +5182,7 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
 	struct device_node *of_node;
 	struct its_node *its;
 	bool has_v4 = false;
+	bool has_v4_1 = false;
 	int err;
 
 	gic_rdists = rdists;
@@ -4838,12 +5203,25 @@ int __init its_init(struct fwnode_handle *handle, struct rdists *rdists,
 	if (err)
 		return err;
 
-	list_for_each_entry(its, &its_nodes, entry)
+	list_for_each_entry(its, &its_nodes, entry) {
 		has_v4 |= is_v4(its);
+		has_v4_1 |= is_v4_1(its);
+	}
+
+	/* Don't bother with inconsistent systems */
+	if (WARN_ON(!has_v4_1 && rdists->has_rvpeid))
+		rdists->has_rvpeid = false;
 
 	if (has_v4 & rdists->has_vlpis) {
+		const struct irq_domain_ops *sgi_ops;
+
+		if (has_v4_1)
+			sgi_ops = &its_sgi_domain_ops;
+		else
+			sgi_ops = NULL;
+
 		if (its_init_vpe_domain() ||
-		    its_init_v4(parent_domain, &its_vpe_domain_ops)) {
+		    its_init_v4(parent_domain, &its_vpe_domain_ops, sgi_ops)) {
 			rdists->has_vlpis = false;
 			pr_err("ITS: Disabling GICv4 support\n");
 		}

drivers/irqchip/irq-gic-v3.c

@@ -723,6 +723,7 @@ static void __init gic_dist_init(void)
 	unsigned int i;
 	u64 affinity;
 	void __iomem *base = gic_data.dist_base;
+	u32 val;
 
 	/* Disable the distributor */
 	writel_relaxed(0, base + GICD_CTLR);
@@ -755,9 +756,14 @@ static void __init gic_dist_init(void)
 	/* Now do the common stuff, and wait for the distributor to drain */
 	gic_dist_config(base, GIC_LINE_NR, gic_dist_wait_for_rwp);
 
+	val = GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A | GICD_CTLR_ENABLE_G1;
+	if (gic_data.rdists.gicd_typer2 & GICD_TYPER2_nASSGIcap) {
+		pr_info("Enabling SGIs without active state\n");
+		val |= GICD_CTLR_nASSGIreq;
+	}
+
 	/* Enable distributor with ARE, Group1 */
-	writel_relaxed(GICD_CTLR_ARE_NS | GICD_CTLR_ENABLE_G1A | GICD_CTLR_ENABLE_G1,
-		       base + GICD_CTLR);
+	writel_relaxed(val, base + GICD_CTLR);
 
 	/*
 	 * Set all global interrupts to the boot CPU only. ARE must be
@@ -828,6 +834,7 @@ static int __gic_populate_rdist(struct redist_region *region, void __iomem *ptr)
 	typer = gic_read_typer(ptr + GICR_TYPER);
 	if ((typer >> 32) == aff) {
 		u64 offset = ptr - region->redist_base;
+		raw_spin_lock_init(&gic_data_rdist()->rd_lock);
 		gic_data_rdist_rd_base() = ptr;
 		gic_data_rdist()->phys_base = region->phys_base + offset;
 
@@ -1757,6 +1764,7 @@ static void __init gic_of_setup_kvm_info(struct device_node *node)
 		gic_v3_kvm_info.vcpu = r;
 
 	gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis;
+	gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid;
 	gic_set_kvm_info(&gic_v3_kvm_info);
 }
 
@@ -2072,6 +2080,7 @@ static void __init gic_acpi_setup_kvm_info(void)
 	}
 
 	gic_v3_kvm_info.has_v4 = gic_data.rdists.has_vlpis;
+	gic_v3_kvm_info.has_v4_1 = gic_data.rdists.has_rvpeid;
 	gic_set_kvm_info(&gic_v3_kvm_info);
 }
 

drivers/irqchip/irq-gic-v4.c

@@ -85,6 +85,53 @@
 
 static struct irq_domain *gic_domain;
 static const struct irq_domain_ops *vpe_domain_ops;
+static const struct irq_domain_ops *sgi_domain_ops;
+
+static bool has_v4_1(void)
+{
+	return !!sgi_domain_ops;
+}
+
+static int its_alloc_vcpu_sgis(struct its_vpe *vpe, int idx)
+{
+	char *name;
+	int sgi_base;
+
+	if (!has_v4_1())
+		return 0;
+
+	name = kasprintf(GFP_KERNEL, "GICv4-sgi-%d", task_pid_nr(current));
+	if (!name)
+		goto err;
+
+	vpe->fwnode = irq_domain_alloc_named_id_fwnode(name, idx);
+	if (!vpe->fwnode)
+		goto err;
+
+	kfree(name);
+	name = NULL;
+
+	vpe->sgi_domain = irq_domain_create_linear(vpe->fwnode, 16,
+						   sgi_domain_ops, vpe);
+	if (!vpe->sgi_domain)
+		goto err;
+
+	sgi_base = __irq_domain_alloc_irqs(vpe->sgi_domain, -1, 16,
+					       NUMA_NO_NODE, vpe,
+					       false, NULL);
+	if (sgi_base <= 0)
+		goto err;
+
+	return 0;
+
+err:
+	if (vpe->sgi_domain)
+		irq_domain_remove(vpe->sgi_domain);
+	if (vpe->fwnode)
+		irq_domain_free_fwnode(vpe->fwnode);
+	kfree(name);
+	return -ENOMEM;
+}
 
 int its_alloc_vcpu_irqs(struct its_vm *vm)
 {
@@ -112,8 +159,13 @@ int its_alloc_vcpu_irqs(struct its_vm *vm)
 	if (vpe_base_irq <= 0)
 		goto err;
 
-	for (i = 0; i < vm->nr_vpes; i++)
+	for (i = 0; i < vm->nr_vpes; i++) {
+		int ret;
 		vm->vpes[i]->irq = vpe_base_irq + i;
+		ret = its_alloc_vcpu_sgis(vm->vpes[i], i);
+		if (ret)
+			goto err;
+	}
 
 	return 0;
 
@@ -126,8 +178,28 @@ int its_alloc_vcpu_irqs(struct its_vm *vm)
 	return -ENOMEM;
 }
 
+static void its_free_sgi_irqs(struct its_vm *vm)
+{
+	int i;
+
+	if (!has_v4_1())
+		return;
+
+	for (i = 0; i < vm->nr_vpes; i++) {
+		unsigned int irq = irq_find_mapping(vm->vpes[i]->sgi_domain, 0);
+
+		if (WARN_ON(!irq))
+			continue;
+
+		irq_domain_free_irqs(irq, 16);
+		irq_domain_remove(vm->vpes[i]->sgi_domain);
+		irq_domain_free_fwnode(vm->vpes[i]->fwnode);
+	}
+}
+
 void its_free_vcpu_irqs(struct its_vm *vm)
 {
+	its_free_sgi_irqs(vm);
 	irq_domain_free_irqs(vm->vpes[0]->irq, vm->nr_vpes);
 	irq_domain_remove(vm->domain);
 	irq_domain_free_fwnode(vm->fwnode);
@@ -138,18 +210,50 @@ static int its_send_vpe_cmd(struct its_vpe *vpe, struct its_cmd_info *info)
 	return irq_set_vcpu_affinity(vpe->irq, info);
 }
 
-int its_schedule_vpe(struct its_vpe *vpe, bool on)
+int its_make_vpe_non_resident(struct its_vpe *vpe, bool db)
+{
+	struct irq_desc *desc = irq_to_desc(vpe->irq);
+	struct its_cmd_info info = { };
+	int ret;
+
+	WARN_ON(preemptible());
+
+	info.cmd_type = DESCHEDULE_VPE;
+	if (has_v4_1()) {
+		/* GICv4.1 can directly deal with doorbells */
+		info.req_db = db;
+	} else {
+		/* Undo the nested disable_irq() calls... */
+		while (db && irqd_irq_disabled(&desc->irq_data))
+			enable_irq(vpe->irq);
+	}
+
+	ret = its_send_vpe_cmd(vpe, &info);
+	if (!ret)
+		vpe->resident = false;
+
+	return ret;
+}
+
+int its_make_vpe_resident(struct its_vpe *vpe, bool g0en, bool g1en)
 {
-	struct its_cmd_info info;
+	struct its_cmd_info info = { };
 	int ret;
 
 	WARN_ON(preemptible());
 
-	info.cmd_type = on ? SCHEDULE_VPE : DESCHEDULE_VPE;
+	info.cmd_type = SCHEDULE_VPE;
+	if (has_v4_1()) {
+		info.g0en = g0en;
+		info.g1en = g1en;
+	} else {
+		/* Disabled the doorbell, as we're about to enter the guest */
+		disable_irq_nosync(vpe->irq);
+	}
 
 	ret = its_send_vpe_cmd(vpe, &info);
 	if (!ret)
-		vpe->resident = on;
+		vpe->resident = true;
 
 	return ret;
 }
@@ -216,12 +320,28 @@ int its_prop_update_vlpi(int irq, u8 config, bool inv)
 	return irq_set_vcpu_affinity(irq, &info);
 }
 
-int its_init_v4(struct irq_domain *domain, const struct irq_domain_ops *ops)
+int its_prop_update_vsgi(int irq, u8 priority, bool group)
+{
+	struct its_cmd_info info = {
+		.cmd_type = PROP_UPDATE_VSGI,
+		{
+			.priority	= priority,
+			.group		= group,
+		},
+	};
+
+	return irq_set_vcpu_affinity(irq, &info);
+}
+
+int its_init_v4(struct irq_domain *domain,
+		const struct irq_domain_ops *vpe_ops,
+		const struct irq_domain_ops *sgi_ops)
 {
 	if (domain) {
 		pr_info("ITS: Enabling GICv4 support\n");
 		gic_domain = domain;
-		vpe_domain_ops = ops;
+		vpe_domain_ops = vpe_ops;
+		sgi_domain_ops = sgi_ops;
 		return 0;
 	}
 

include/kvm/arm_vgic.h

@@ -70,6 +70,7 @@ struct vgic_global {
 
 	/* Hardware has GICv4? */
 	bool			has_gicv4;
+	bool			has_gicv4_1;
 
 	/* GIC system register CPU interface */
 	struct static_key_false gicv3_cpuif;
@@ -230,6 +231,9 @@ struct vgic_dist {
 	/* distributor enabled */
 	bool			enabled;
 
+	/* Wants SGIs without active state */
+	bool			nassgireq;
+
 	struct vgic_irq		*spis;
 
 	struct vgic_io_device	dist_iodev;

include/linux/irqchip/arm-gic-common.h

@@ -32,6 +32,8 @@ struct gic_kvm_info {
 	struct resource vctrl;
 	/* vlpi support */
 	bool		has_v4;
+	/* rvpeid support */
+	bool		has_v4_1;
 };
 
 const struct gic_kvm_info *gic_get_kvm_info(void);

include/linux/irqchip/arm-gic-v3.h

@@ -57,6 +57,7 @@
 #define GICD_SPENDSGIR			0x0F20
 
 #define GICD_CTLR_RWP			(1U << 31)
+#define GICD_CTLR_nASSGIreq		(1U << 8)
 #define GICD_CTLR_DS			(1U << 6)
 #define GICD_CTLR_ARE_NS		(1U << 4)
 #define GICD_CTLR_ENABLE_G1A		(1U << 1)
@@ -90,6 +91,7 @@
 #define GICD_TYPER_ESPIS(typer)						\
 	(((typer) & GICD_TYPER_ESPI) ? GICD_TYPER_SPIS((typer) >> 27) : 0)
 
+#define GICD_TYPER2_nASSGIcap		(1U << 8)
 #define GICD_TYPER2_VIL			(1U << 7)
 #define GICD_TYPER2_VID			GENMASK(4, 0)
 
@@ -343,6 +345,15 @@
 #define GICR_VPENDBASER_4_1_VGRP1EN	(1ULL << 58)
 #define GICR_VPENDBASER_4_1_VPEID	GENMASK_ULL(15, 0)
 
+#define GICR_VSGIR			0x0080
+
+#define GICR_VSGIR_VPEID		GENMASK(15, 0)
+
+#define GICR_VSGIPENDR			0x0088
+
+#define GICR_VSGIPENDR_BUSY		(1U << 31)
+#define GICR_VSGIPENDR_PENDING		GENMASK(15, 0)
+
 /*
  * ITS registers, offsets from ITS_base
  */
@@ -366,6 +377,11 @@
 
 #define GITS_TRANSLATER			0x10040
 
+#define GITS_SGIR			0x20020
+
+#define GITS_SGIR_VPEID			GENMASK_ULL(47, 32)
+#define GITS_SGIR_VINTID		GENMASK_ULL(3, 0)
+
 #define GITS_CTLR_ENABLE		(1U << 0)
 #define GITS_CTLR_ImDe			(1U << 1)
 #define	GITS_CTLR_ITS_NUMBER_SHIFT	4
@@ -500,8 +516,9 @@
 #define GITS_CMD_VMAPTI			GITS_CMD_GICv4(GITS_CMD_MAPTI)
 #define GITS_CMD_VMOVI			GITS_CMD_GICv4(GITS_CMD_MOVI)
 #define GITS_CMD_VSYNC			GITS_CMD_GICv4(GITS_CMD_SYNC)
-/* VMOVP and INVDB are the odd ones, as they dont have a physical counterpart */
+/* VMOVP, VSGI and INVDB are the odd ones, as they dont have a physical counterpart */
 #define GITS_CMD_VMOVP			GITS_CMD_GICv4(2)
+#define GITS_CMD_VSGI			GITS_CMD_GICv4(3)
 #define GITS_CMD_INVDB			GITS_CMD_GICv4(0xe)
 
 /*
@@ -650,6 +667,7 @@
 
 struct rdists {
 	struct {
+		raw_spinlock_t	rd_lock;
 		void __iomem	*rd_base;
 		struct page	*pend_page;
 		phys_addr_t	phys_base;

include/linux/irqchip/arm-gic-v4.h

@@ -49,10 +49,22 @@ struct its_vpe {
 		};
 		/* GICv4.1 implementations */
 		struct {
+			struct fwnode_handle	*fwnode;
+			struct irq_domain	*sgi_domain;
+			struct {
+				u8	priority;
+				bool	enabled;
+				bool	group;
+			}			sgi_config[16];
 			atomic_t vmapp_count;
 		};
 	};
 
+	/*
+	 * Ensures mutual exclusion between affinity setting of the
+	 * vPE and vLPI operations using vpe->col_idx.
+	 */
+	raw_spinlock_t		vpe_lock;
 	/*
 	 * This collection ID is used to indirect the target
 	 * redistributor for this VPE. The ID itself isn't involved in
@@ -93,6 +105,7 @@ enum its_vcpu_info_cmd_type {
 	SCHEDULE_VPE,
 	DESCHEDULE_VPE,
 	INVALL_VPE,
+	PROP_UPDATE_VSGI,
 };
 
 struct its_cmd_info {
@@ -105,19 +118,27 @@ struct its_cmd_info {
 			bool		g0en;
 			bool		g1en;
 		};
+		struct {
+			u8		priority;
+			bool		group;
+		};
 	};
 };
 
 int its_alloc_vcpu_irqs(struct its_vm *vm);
 void its_free_vcpu_irqs(struct its_vm *vm);
-int its_schedule_vpe(struct its_vpe *vpe, bool on);
+int its_make_vpe_resident(struct its_vpe *vpe, bool g0en, bool g1en);
+int its_make_vpe_non_resident(struct its_vpe *vpe, bool db);
 int its_invall_vpe(struct its_vpe *vpe);
 int its_map_vlpi(int irq, struct its_vlpi_map *map);
 int its_get_vlpi(int irq, struct its_vlpi_map *map);
 int its_unmap_vlpi(int irq);
 int its_prop_update_vlpi(int irq, u8 config, bool inv);
+int its_prop_update_vsgi(int irq, u8 priority, bool group);
 
 struct irq_domain_ops;
-int its_init_v4(struct irq_domain *domain, const struct irq_domain_ops *ops);
+int its_init_v4(struct irq_domain *domain,
+		const struct irq_domain_ops *vpe_ops,
+		const struct irq_domain_ops *sgi_ops);
 
 #endif

virt/kvm/arm/arm.c

@@ -625,6 +625,14 @@ static void check_vcpu_requests(struct kvm_vcpu *vcpu)
 
 		if (kvm_check_request(KVM_REQ_RECORD_STEAL, vcpu))
 			kvm_update_stolen_time(vcpu);
+
+		if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) {
+			/* The distributor enable bits were changed */
+			preempt_disable();
+			vgic_v4_put(vcpu, false);
+			vgic_v4_load(vcpu);
+			preempt_enable();
+		}
 	}
 }
 

virt/kvm/arm/vgic/vgic-debug.c

@@ -178,6 +178,8 @@ static void print_irq_state(struct seq_file *s, struct vgic_irq *irq,
 			    struct kvm_vcpu *vcpu)
 {
 	char *type;
+	bool pending;
+
 	if (irq->intid < VGIC_NR_SGIS)
 		type = "SGI";
 	else if (irq->intid < VGIC_NR_PRIVATE_IRQS)
@@ -190,6 +192,16 @@ static void print_irq_state(struct seq_file *s, struct vgic_irq *irq,
 	if (irq->intid ==0 || irq->intid == VGIC_NR_PRIVATE_IRQS)
 		print_header(s, irq, vcpu);
 
+	pending = irq->pending_latch;
+	if (irq->hw && vgic_irq_is_sgi(irq->intid)) {
+		int err;
+
+		err = irq_get_irqchip_state(irq->host_irq,
+					    IRQCHIP_STATE_PENDING,
+					    &pending);
+		WARN_ON_ONCE(err);
+	}
+
 	seq_printf(s, "       %s %4d "
 		      "    %2d "
 		      "%d%d%d%d%d%d%d "
@@ -201,7 +213,7 @@ static void print_irq_state(struct seq_file *s, struct vgic_irq *irq,
 		      "\n",
 			type, irq->intid,
 			(irq->target_vcpu) ? irq->target_vcpu->vcpu_id : -1,
-			irq->pending_latch,
+			pending,
 			irq->line_level,
 			irq->active,
 			irq->enabled,

virt/kvm/arm/vgic/vgic-mmio-v3.c

@@ -3,9 +3,11 @@
  * VGICv3 MMIO handling functions
  */
 
+#include <linux/bitfield.h>
 #include <linux/irqchip/arm-gic-v3.h>
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
+#include <linux/interrupt.h>
 #include <kvm/iodev.h>
 #include <kvm/arm_vgic.h>
 
@@ -69,6 +71,8 @@ static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu,
 		if (vgic->enabled)
 			value |= GICD_CTLR_ENABLE_SS_G1;
 		value |= GICD_CTLR_ARE_NS | GICD_CTLR_DS;
+		if (vgic->nassgireq)
+			value |= GICD_CTLR_nASSGIreq;
 		break;
 	case GICD_TYPER:
 		value = vgic->nr_spis + VGIC_NR_PRIVATE_IRQS;
@@ -80,6 +84,10 @@ static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu,
 			value |= (INTERRUPT_ID_BITS_SPIS - 1) << 19;
 		}
 		break;
+	case GICD_TYPER2:
+		if (kvm_vgic_global_state.has_gicv4_1)
+			value = GICD_TYPER2_nASSGIcap;
+		break;
 	case GICD_IIDR:
 		value = (PRODUCT_ID_KVM << GICD_IIDR_PRODUCT_ID_SHIFT) |
 			(vgic->implementation_rev << GICD_IIDR_REVISION_SHIFT) |
@@ -97,17 +105,46 @@ static void vgic_mmio_write_v3_misc(struct kvm_vcpu *vcpu,
 				    unsigned long val)
 {
 	struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
-	bool was_enabled = dist->enabled;
 
 	switch (addr & 0x0c) {
-	case GICD_CTLR:
+	case GICD_CTLR: {
+		bool was_enabled, is_hwsgi;
+
+		mutex_lock(&vcpu->kvm->lock);
+
+		was_enabled = dist->enabled;
+		is_hwsgi = dist->nassgireq;
+
 		dist->enabled = val & GICD_CTLR_ENABLE_SS_G1;
 
-		if (!was_enabled && dist->enabled)
+		/* Not a GICv4.1? No HW SGIs */
+		if (!kvm_vgic_global_state.has_gicv4_1)
+			val &= ~GICD_CTLR_nASSGIreq;
+
+		/* Dist stays enabled? nASSGIreq is RO */
+		if (was_enabled && dist->enabled) {
+			val &= ~GICD_CTLR_nASSGIreq;
+			val |= FIELD_PREP(GICD_CTLR_nASSGIreq, is_hwsgi);
+		}
+
+		/* Switching HW SGIs? */
+		dist->nassgireq = val & GICD_CTLR_nASSGIreq;
+		if (is_hwsgi != dist->nassgireq)
+			vgic_v4_configure_vsgis(vcpu->kvm);
+
+		if (kvm_vgic_global_state.has_gicv4_1 &&
+		    was_enabled != dist->enabled)
+			kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_RELOAD_GICv4);
+		else if (!was_enabled && dist->enabled)
 			vgic_kick_vcpus(vcpu->kvm);
+
+		mutex_unlock(&vcpu->kvm->lock);
 		break;
+	}
 	case GICD_TYPER:
+	case GICD_TYPER2:
 	case GICD_IIDR:
+		/* This is at best for documentation purposes... */
 		return;
 	}
 }
@@ -116,10 +153,22 @@ static int vgic_mmio_uaccess_write_v3_misc(struct kvm_vcpu *vcpu,
 					   gpa_t addr, unsigned int len,
 					   unsigned long val)
 {
+	struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
 	switch (addr & 0x0c) {
+	case GICD_TYPER2:
 	case GICD_IIDR:
 		if (val != vgic_mmio_read_v3_misc(vcpu, addr, len))
 			return -EINVAL;
+		return 0;
+	case GICD_CTLR:
+		/* Not a GICv4.1? No HW SGIs */
+		if (!kvm_vgic_global_state.has_gicv4_1)
+			val &= ~GICD_CTLR_nASSGIreq;
+
+		dist->enabled = val & GICD_CTLR_ENABLE_SS_G1;
+		dist->nassgireq = val & GICD_CTLR_nASSGIreq;
+		return 0;
 	}
 
 	vgic_mmio_write_v3_misc(vcpu, addr, len, val);
@@ -257,8 +306,18 @@ static unsigned long vgic_v3_uaccess_read_pending(struct kvm_vcpu *vcpu,
 	 */
 	for (i = 0; i < len * 8; i++) {
 		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
+		bool state = irq->pending_latch;
 
-		if (irq->pending_latch)
+		if (irq->hw && vgic_irq_is_sgi(irq->intid)) {
+			int err;
+
+			err = irq_get_irqchip_state(irq->host_irq,
+						    IRQCHIP_STATE_PENDING,
+						    &state);
+			WARN_ON(err);
+		}
+
+		if (state)
 			value |= (1U << i);
 
 		vgic_put_irq(vcpu->kvm, irq);
@@ -942,8 +1001,18 @@ void vgic_v3_dispatch_sgi(struct kvm_vcpu *vcpu, u64 reg, bool allow_group1)
 		 * generate interrupts of either group.
 		 */
 		if (!irq->group || allow_group1) {
-			irq->pending_latch = true;
-			vgic_queue_irq_unlock(vcpu->kvm, irq, flags);
+			if (!irq->hw) {
+				irq->pending_latch = true;
+				vgic_queue_irq_unlock(vcpu->kvm, irq, flags);
+			} else {
+				/* HW SGI? Ask the GIC to inject it */
+				int err;
+				err = irq_set_irqchip_state(irq->host_irq,
+							    IRQCHIP_STATE_PENDING,
+							    true);
+				WARN_RATELIMIT(err, "IRQ %d", irq->host_irq);
+				raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
+			}
 		} else {
 			raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 		}

virt/kvm/arm/vgic/vgic-mmio.c

@@ -5,6 +5,8 @@
 
 #include <linux/bitops.h>
 #include <linux/bsearch.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
 #include <kvm/iodev.h>
@@ -59,6 +61,11 @@ unsigned long vgic_mmio_read_group(struct kvm_vcpu *vcpu,
 	return value;
 }
 
+static void vgic_update_vsgi(struct vgic_irq *irq)
+{
+	WARN_ON(its_prop_update_vsgi(irq->host_irq, irq->priority, irq->group));
+}
+
 void vgic_mmio_write_group(struct kvm_vcpu *vcpu, gpa_t addr,
 			   unsigned int len, unsigned long val)
 {
@@ -71,7 +78,12 @@ void vgic_mmio_write_group(struct kvm_vcpu *vcpu, gpa_t addr,
 
 		raw_spin_lock_irqsave(&irq->irq_lock, flags);
 		irq->group = !!(val & BIT(i));
-		vgic_queue_irq_unlock(vcpu->kvm, irq, flags);
+		if (irq->hw && vgic_irq_is_sgi(irq->intid)) {
+			vgic_update_vsgi(irq);
+			raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
+		} else {
+			vgic_queue_irq_unlock(vcpu->kvm, irq, flags);
+		}
 
 		vgic_put_irq(vcpu->kvm, irq);
 	}
@@ -113,7 +125,21 @@ void vgic_mmio_write_senable(struct kvm_vcpu *vcpu,
 		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
 
 		raw_spin_lock_irqsave(&irq->irq_lock, flags);
-		if (vgic_irq_is_mapped_level(irq)) {
+		if (irq->hw && vgic_irq_is_sgi(irq->intid)) {
+			if (!irq->enabled) {
+				struct irq_data *data;
+
+				irq->enabled = true;
+				data = &irq_to_desc(irq->host_irq)->irq_data;
+				while (irqd_irq_disabled(data))
+					enable_irq(irq->host_irq);
+			}
+
+			raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
+			vgic_put_irq(vcpu->kvm, irq);
+
+			continue;
+		} else if (vgic_irq_is_mapped_level(irq)) {
 			bool was_high = irq->line_level;
 
 			/*
@@ -148,6 +174,8 @@ void vgic_mmio_write_cenable(struct kvm_vcpu *vcpu,
 		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
 
 		raw_spin_lock_irqsave(&irq->irq_lock, flags);
+		if (irq->hw && vgic_irq_is_sgi(irq->intid) && irq->enabled)
+			disable_irq_nosync(irq->host_irq);
 
 		irq->enabled = false;
 
@@ -167,10 +195,22 @@ unsigned long vgic_mmio_read_pending(struct kvm_vcpu *vcpu,
 	for (i = 0; i < len * 8; i++) {
 		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, intid + i);
 		unsigned long flags;
+		bool val;
 
 		raw_spin_lock_irqsave(&irq->irq_lock, flags);
-		if (irq_is_pending(irq))
-			value |= (1U << i);
+		if (irq->hw && vgic_irq_is_sgi(irq->intid)) {
+			int err;
+
+			val = false;
+			err = irq_get_irqchip_state(irq->host_irq,
+						    IRQCHIP_STATE_PENDING,
+						    &val);
+			WARN_RATELIMIT(err, "IRQ %d", irq->host_irq);
+		} else {
+			val = irq_is_pending(irq);
+		}
+
+		value |= ((u32)val << i);
 		raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 
 		vgic_put_irq(vcpu->kvm, irq);
@@ -215,6 +255,21 @@ void vgic_mmio_write_spending(struct kvm_vcpu *vcpu,
 		}
 
 		raw_spin_lock_irqsave(&irq->irq_lock, flags);
+
+		if (irq->hw && vgic_irq_is_sgi(irq->intid)) {
+			/* HW SGI? Ask the GIC to inject it */
+			int err;
+			err = irq_set_irqchip_state(irq->host_irq,
+						    IRQCHIP_STATE_PENDING,
+						    true);
+			WARN_RATELIMIT(err, "IRQ %d", irq->host_irq);
+
+			raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
+			vgic_put_irq(vcpu->kvm, irq);
+
+			continue;
+		}
+
 		if (irq->hw)
 			vgic_hw_irq_spending(vcpu, irq, is_uaccess);
 		else
@@ -269,6 +324,20 @@ void vgic_mmio_write_cpending(struct kvm_vcpu *vcpu,
 
 		raw_spin_lock_irqsave(&irq->irq_lock, flags);
 
+		if (irq->hw && vgic_irq_is_sgi(irq->intid)) {
+			/* HW SGI? Ask the GIC to clear its pending bit */
+			int err;
+			err = irq_set_irqchip_state(irq->host_irq,
+						    IRQCHIP_STATE_PENDING,
+						    false);
+			WARN_RATELIMIT(err, "IRQ %d", irq->host_irq);
+
+			raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
+			vgic_put_irq(vcpu->kvm, irq);
+
+			continue;
+		}
+
 		if (irq->hw)
 			vgic_hw_irq_cpending(vcpu, irq, is_uaccess);
 		else
@@ -318,8 +387,15 @@ static void vgic_mmio_change_active(struct kvm_vcpu *vcpu, struct vgic_irq *irq,
 
 	raw_spin_lock_irqsave(&irq->irq_lock, flags);
 
-	if (irq->hw) {
+	if (irq->hw && !vgic_irq_is_sgi(irq->intid)) {
 		vgic_hw_irq_change_active(vcpu, irq, active, !requester_vcpu);
+	} else if (irq->hw && vgic_irq_is_sgi(irq->intid)) {
+		/*
+		 * GICv4.1 VSGI feature doesn't track an active state,
+		 * so let's not kid ourselves, there is nothing we can
+		 * do here.
+		 */
+		irq->active = false;
 	} else {
 		u32 model = vcpu->kvm->arch.vgic.vgic_model;
 		u8 active_source;
@@ -493,6 +569,8 @@ void vgic_mmio_write_priority(struct kvm_vcpu *vcpu,
 		raw_spin_lock_irqsave(&irq->irq_lock, flags);
 		/* Narrow the priority range to what we actually support */
 		irq->priority = (val >> (i * 8)) & GENMASK(7, 8 - VGIC_PRI_BITS);
+		if (irq->hw && vgic_irq_is_sgi(irq->intid))
+			vgic_update_vsgi(irq);
 		raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
 
 		vgic_put_irq(vcpu->kvm, irq);

virt/kvm/arm/vgic/vgic-v3.c

@@ -540,6 +540,8 @@ int vgic_v3_map_resources(struct kvm *kvm)
 		goto out;
 	}
 
+	if (kvm_vgic_global_state.has_gicv4_1)
+		vgic_v4_configure_vsgis(kvm);
 	dist->ready = true;
 
 out:
@@ -595,7 +597,9 @@ int vgic_v3_probe(const struct gic_kvm_info *info)
 	/* GICv4 support? */
 	if (info->has_v4) {
 		kvm_vgic_global_state.has_gicv4 = gicv4_enable;
-		kvm_info("GICv4 support %sabled\n",
+		kvm_vgic_global_state.has_gicv4_1 = info->has_v4_1 && gicv4_enable;
+		kvm_info("GICv4%s support %sabled\n",
+			 kvm_vgic_global_state.has_gicv4_1 ? ".1" : "",
 			 gicv4_enable ? "en" : "dis");
 	}
 

virt/kvm/arm/vgic/vgic-v4.c

@@ -67,10 +67,10 @@
  * 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.
+ * irq corresponding to the vcpu, then call its_make_vpe_resident().
+ * You must be in a non-preemptible context. On exit, a call to
+ * its_make_vpe_non_resident() 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
@@ -86,7 +86,8 @@ static irqreturn_t vgic_v4_doorbell_handler(int irq, void *info)
 	struct kvm_vcpu *vcpu = info;
 
 	/* We got the message, no need to fire again */
-	if (!irqd_irq_disabled(&irq_to_desc(irq)->irq_data))
+	if (!kvm_vgic_global_state.has_gicv4_1 &&
+	    !irqd_irq_disabled(&irq_to_desc(irq)->irq_data))
 		disable_irq_nosync(irq);
 
 	vcpu->arch.vgic_cpu.vgic_v3.its_vpe.pending_last = true;
@@ -96,6 +97,104 @@ static irqreturn_t vgic_v4_doorbell_handler(int irq, void *info)
 	return IRQ_HANDLED;
 }
 
+static void vgic_v4_sync_sgi_config(struct its_vpe *vpe, struct vgic_irq *irq)
+{
+	vpe->sgi_config[irq->intid].enabled	= irq->enabled;
+	vpe->sgi_config[irq->intid].group 	= irq->group;
+	vpe->sgi_config[irq->intid].priority	= irq->priority;
+}
+
+static void vgic_v4_enable_vsgis(struct kvm_vcpu *vcpu)
+{
+	struct its_vpe *vpe = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe;
+	int i;
+
+	/*
+	 * With GICv4.1, every virtual SGI can be directly injected. So
+	 * let's pretend that they are HW interrupts, tied to a host
+	 * IRQ. The SGI code will do its magic.
+	 */
+	for (i = 0; i < VGIC_NR_SGIS; i++) {
+		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, i);
+		struct irq_desc *desc;
+		unsigned long flags;
+		int ret;
+
+		raw_spin_lock_irqsave(&irq->irq_lock, flags);
+
+		if (irq->hw)
+			goto unlock;
+
+		irq->hw = true;
+		irq->host_irq = irq_find_mapping(vpe->sgi_domain, i);
+
+		/* Transfer the full irq state to the vPE */
+		vgic_v4_sync_sgi_config(vpe, irq);
+		desc = irq_to_desc(irq->host_irq);
+		ret = irq_domain_activate_irq(irq_desc_get_irq_data(desc),
+					      false);
+		if (!WARN_ON(ret)) {
+			/* Transfer pending state */
+			ret = irq_set_irqchip_state(irq->host_irq,
+						    IRQCHIP_STATE_PENDING,
+						    irq->pending_latch);
+			WARN_ON(ret);
+			irq->pending_latch = false;
+		}
+	unlock:
+		raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
+		vgic_put_irq(vcpu->kvm, irq);
+	}
+}
+
+static void vgic_v4_disable_vsgis(struct kvm_vcpu *vcpu)
+{
+	int i;
+
+	for (i = 0; i < VGIC_NR_SGIS; i++) {
+		struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, i);
+		struct irq_desc *desc;
+		unsigned long flags;
+		int ret;
+
+		raw_spin_lock_irqsave(&irq->irq_lock, flags);
+
+		if (!irq->hw)
+			goto unlock;
+
+		irq->hw = false;
+		ret = irq_get_irqchip_state(irq->host_irq,
+					    IRQCHIP_STATE_PENDING,
+					    &irq->pending_latch);
+		WARN_ON(ret);
+
+		desc = irq_to_desc(irq->host_irq);
+		irq_domain_deactivate_irq(irq_desc_get_irq_data(desc));
+	unlock:
+		raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
+		vgic_put_irq(vcpu->kvm, irq);
+	}
+}
+
+/* Must be called with the kvm lock held */
+void vgic_v4_configure_vsgis(struct kvm *kvm)
+{
+	struct vgic_dist *dist = &kvm->arch.vgic;
+	struct kvm_vcpu *vcpu;
+	int i;
+
+	kvm_arm_halt_guest(kvm);
+
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		if (dist->nassgireq)
+			vgic_v4_enable_vsgis(vcpu);
+		else
+			vgic_v4_disable_vsgis(vcpu);
+	}
+
+	kvm_arm_resume_guest(kvm);
+}
+
 /**
  * vgic_v4_init - Initialize the GICv4 data structures
  * @kvm:	Pointer to the VM being initialized
@@ -140,6 +239,7 @@ int vgic_v4_init(struct kvm *kvm)
 
 	kvm_for_each_vcpu(i, vcpu, kvm) {
 		int irq = dist->its_vm.vpes[i]->irq;
+		unsigned long irq_flags = DB_IRQ_FLAGS;
 
 		/*
 		 * Don't automatically enable the doorbell, as we're
@@ -147,8 +247,14 @@ int vgic_v4_init(struct kvm *kvm)
 		 * blocked. Also disable the lazy disabling, as the
 		 * doorbell could kick us out of the guest too
 		 * early...
+		 *
+		 * On GICv4.1, the doorbell is managed in HW and must
+		 * be left enabled.
 		 */
-		irq_set_status_flags(irq, DB_IRQ_FLAGS);
+		if (kvm_vgic_global_state.has_gicv4_1)
+			irq_flags &= ~IRQ_NOAUTOEN;
+		irq_set_status_flags(irq, irq_flags);
+
 		ret = request_irq(irq, vgic_v4_doorbell_handler,
 				  0, "vcpu", vcpu);
 		if (ret) {
@@ -199,19 +305,11 @@ void vgic_v4_teardown(struct kvm *kvm)
 int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db)
 {
 	struct its_vpe *vpe = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe;
-	struct irq_desc *desc = irq_to_desc(vpe->irq);
 
 	if (!vgic_supports_direct_msis(vcpu->kvm) || !vpe->resident)
 		return 0;
 
-	/*
-	 * If blocking, a doorbell is required. Undo the nested
-	 * disable_irq() calls...
-	 */
-	while (need_db && irqd_irq_disabled(&desc->irq_data))
-		enable_irq(vpe->irq);
-
-	return its_schedule_vpe(vpe, false);
+	return its_make_vpe_non_resident(vpe, need_db);
 }
 
 int vgic_v4_load(struct kvm_vcpu *vcpu)
@@ -232,18 +330,19 @@ int vgic_v4_load(struct kvm_vcpu *vcpu)
 	if (err)
 		return err;
 
-	/* Disabled the doorbell, as we're about to enter the guest */
-	disable_irq_nosync(vpe->irq);
-
-	err = its_schedule_vpe(vpe, true);
+	err = its_make_vpe_resident(vpe, false, vcpu->kvm->arch.vgic.enabled);
 	if (err)
 		return err;
 
 	/*
 	 * Now that the VPE is resident, let's get rid of a potential
-	 * doorbell interrupt that would still be pending.
+	 * doorbell interrupt that would still be pending. This is a
+	 * GICv4.0 only "feature"...
 	 */
-	return irq_set_irqchip_state(vpe->irq, IRQCHIP_STATE_PENDING, false);
+	if (!kvm_vgic_global_state.has_gicv4_1)
+		err = irq_set_irqchip_state(vpe->irq, IRQCHIP_STATE_PENDING, false);
+
+	return err;
 }
 
 static struct vgic_its *vgic_get_its(struct kvm *kvm,

virt/kvm/arm/vgic/vgic.h

@@ -316,5 +316,6 @@ void vgic_its_invalidate_cache(struct kvm *kvm);
 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);
 
 #endif