Merge tag 'iommu-fixes-6.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu fixes from Joerg Roedel:

 - Maintainer update for S390 IOMMU driver

 - A fix for the set_platform_dma_ops() call-back in the Exynos
   IOMMU driver

 - Intel VT-d fixes from Lu Baolu:
    - Fix a lockdep splat
    - Fix a supplement of the specification
    - Fix a warning in perfmon code

* tag 'iommu-fixes-6.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Fix an IOMMU perfmon warning when CPU hotplug
  iommu/vt-d: Allow zero SAGAW if second-stage not supported
  iommu/vt-d: Remove unnecessary locking in intel_irq_remapping_alloc()
  iommu/exynos: Fix set_platform_dma_ops() callback
  MAINTAINERS: Update s390-iommu driver maintainer information

7 files changed, 60 insertions, 40 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index e01e546f3a90..26e5ad517532 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -18288,8 +18288,9 @@ F:	drivers/s390/block/dasd*
 F:	include/linux/dasd_mod.h
 
 S390 IOMMU (PCI)
+M:	Niklas Schnelle <schnelle@linux.ibm.com>
 M:	Matthew Rosato <mjrosato@linux.ibm.com>
-M:	Gerald Schaefer <gerald.schaefer@linux.ibm.com>
+R:	Gerald Schaefer <gerald.schaefer@linux.ibm.com>
 L:	linux-s390@vger.kernel.org
 S:	Supported
 F:	drivers/iommu/s390-iommu.c
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 483aaaeb6dae..1abd187c6075 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -1415,23 +1415,26 @@ static struct iommu_device *exynos_iommu_probe_device(struct device *dev)
 	return &data->iommu;
 }
 
-static void exynos_iommu_release_device(struct device *dev)
+static void exynos_iommu_set_platform_dma(struct device *dev)
 {
 	struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
-	struct sysmmu_drvdata *data;
 
 	if (owner->domain) {
 		struct iommu_group *group = iommu_group_get(dev);
 
 		if (group) {
-#ifndef CONFIG_ARM
-			WARN_ON(owner->domain !=
-				iommu_group_default_domain(group));
-#endif
 			exynos_iommu_detach_device(owner->domain, dev);
 			iommu_group_put(group);
 		}
 	}
+}
+
+static void exynos_iommu_release_device(struct device *dev)
+{
+	struct exynos_iommu_owner *owner = dev_iommu_priv_get(dev);
+	struct sysmmu_drvdata *data;
+
+	exynos_iommu_set_platform_dma(dev);
 
 	list_for_each_entry(data, &owner->controllers, owner_node)
 		device_link_del(data->link);
@@ -1479,7 +1482,7 @@ static const struct iommu_ops exynos_iommu_ops = {
 	.domain_alloc = exynos_iommu_domain_alloc,
 	.device_group = generic_device_group,
 #ifdef CONFIG_ARM
-	.set_platform_dma_ops = exynos_iommu_release_device,
+	.set_platform_dma_ops = exynos_iommu_set_platform_dma,
 #endif
 	.probe_device = exynos_iommu_probe_device,
 	.release_device = exynos_iommu_release_device,
diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index 6acfe879589c..23828d189c2a 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -1071,7 +1071,8 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd)
 	}
 
 	err = -EINVAL;
-	if (cap_sagaw(iommu->cap) == 0) {
+	if (!cap_sagaw(iommu->cap) &&
+	    (!ecap_smts(iommu->ecap) || ecap_slts(iommu->ecap))) {
 		pr_info("%s: No supported address widths. Not attempting DMA translation.\n",
 			iommu->name);
 		drhd->ignored = 1;
diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
index d6df3b865812..694ab9b7d3e9 100644
--- a/drivers/iommu/intel/iommu.h
+++ b/drivers/iommu/intel/iommu.h
@@ -641,6 +641,8 @@ struct iommu_pmu {
 	DECLARE_BITMAP(used_mask, IOMMU_PMU_IDX_MAX);
 	struct perf_event	*event_list[IOMMU_PMU_IDX_MAX];
 	unsigned char		irq_name[16];
+	struct hlist_node	cpuhp_node;
+	int			cpu;
 };
 
 #define IOMMU_IRQ_ID_OFFSET_PRQ		(DMAR_UNITS_SUPPORTED)
diff --git a/drivers/iommu/intel/irq_remapping.c b/drivers/iommu/intel/irq_remapping.c
index 6d01fa078c36..df9e261af0b5 100644
--- a/drivers/iommu/intel/irq_remapping.c
+++ b/drivers/iommu/intel/irq_remapping.c
@@ -311,14 +311,12 @@ static int set_ioapic_sid(struct irte *irte, int apic)
 	if (!irte)
 		return -1;
 
-	down_read(&dmar_global_lock);
 	for (i = 0; i < MAX_IO_APICS; i++) {
 		if (ir_ioapic[i].iommu && ir_ioapic[i].id == apic) {
 			sid = (ir_ioapic[i].bus << 8) | ir_ioapic[i].devfn;
 			break;
 		}
 	}
-	up_read(&dmar_global_lock);
 
 	if (sid == 0) {
 		pr_warn("Failed to set source-id of IOAPIC (%d)\n", apic);
@@ -338,14 +336,12 @@ static int set_hpet_sid(struct irte *irte, u8 id)
 	if (!irte)
 		return -1;
 
-	down_read(&dmar_global_lock);
 	for (i = 0; i < MAX_HPET_TBS; i++) {
 		if (ir_hpet[i].iommu && ir_hpet[i].id == id) {
 			sid = (ir_hpet[i].bus << 8) | ir_hpet[i].devfn;
 			break;
 		}
 	}
-	up_read(&dmar_global_lock);
 
 	if (sid == 0) {
 		pr_warn("Failed to set source-id of HPET block (%d)\n", id);
@@ -1339,9 +1335,7 @@ static int intel_irq_remapping_alloc(struct irq_domain *domain,
 	if (!data)
 		goto out_free_parent;
 
-	down_read(&dmar_global_lock);
 	index = alloc_irte(iommu, &data->irq_2_iommu, nr_irqs);
-	up_read(&dmar_global_lock);
 	if (index < 0) {
 		pr_warn("Failed to allocate IRTE\n");
 		kfree(data);
diff --git a/drivers/iommu/intel/perfmon.c b/drivers/iommu/intel/perfmon.c
index e17d9743a0d8..cf43e798eca4 100644
--- a/drivers/iommu/intel/perfmon.c
+++ b/drivers/iommu/intel/perfmon.c
@@ -773,19 +773,34 @@ static void iommu_pmu_unset_interrupt(struct intel_iommu *iommu)
 	iommu->perf_irq = 0;
 }
 
-static int iommu_pmu_cpu_online(unsigned int cpu)
+static int iommu_pmu_cpu_online(unsigned int cpu, struct hlist_node *node)
 {
+	struct iommu_pmu *iommu_pmu = hlist_entry_safe(node, typeof(*iommu_pmu), cpuhp_node);
+
 	if (cpumask_empty(&iommu_pmu_cpu_mask))
 		cpumask_set_cpu(cpu, &iommu_pmu_cpu_mask);
 
+	if (cpumask_test_cpu(cpu, &iommu_pmu_cpu_mask))
+		iommu_pmu->cpu = cpu;
+
 	return 0;
 }
 
-static int iommu_pmu_cpu_offline(unsigned int cpu)
+static int iommu_pmu_cpu_offline(unsigned int cpu, struct hlist_node *node)
 {
-	struct dmar_drhd_unit *drhd;
-	struct intel_iommu *iommu;
-	int target;
+	struct iommu_pmu *iommu_pmu = hlist_entry_safe(node, typeof(*iommu_pmu), cpuhp_node);
+	int target = cpumask_first(&iommu_pmu_cpu_mask);
+
+	/*
+	 * The iommu_pmu_cpu_mask has been updated when offline the CPU
+	 * for the first iommu_pmu. Migrate the other iommu_pmu to the
+	 * new target.
+	 */
+	if (target < nr_cpu_ids && target != iommu_pmu->cpu) {
+		perf_pmu_migrate_context(&iommu_pmu->pmu, cpu, target);
+		iommu_pmu->cpu = target;
+		return 0;
+	}
 
 	if (!cpumask_test_and_clear_cpu(cpu, &iommu_pmu_cpu_mask))
 		return 0;
@@ -795,45 +810,50 @@ static int iommu_pmu_cpu_offline(unsigned int cpu)
 	if (target < nr_cpu_ids)
 		cpumask_set_cpu(target, &iommu_pmu_cpu_mask);
 	else
-		target = -1;
+		return 0;
 
-	rcu_read_lock();
-
-	for_each_iommu(iommu, drhd) {
-		if (!iommu->pmu)
-			continue;
-		perf_pmu_migrate_context(&iommu->pmu->pmu, cpu, target);
-	}
-	rcu_read_unlock();
+	perf_pmu_migrate_context(&iommu_pmu->pmu, cpu, target);
+	iommu_pmu->cpu = target;
 
 	return 0;
 }
 
 static int nr_iommu_pmu;
+static enum cpuhp_state iommu_cpuhp_slot;
 
 static int iommu_pmu_cpuhp_setup(struct iommu_pmu *iommu_pmu)
 {
 	int ret;
 
-	if (nr_iommu_pmu++)
-		return 0;
+	if (!nr_iommu_pmu) {
+		ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
+					      "driver/iommu/intel/perfmon:online",
+					      iommu_pmu_cpu_online,
+					      iommu_pmu_cpu_offline);
+		if (ret < 0)
+			return ret;
+		iommu_cpuhp_slot = ret;
+	}
 
-	ret = cpuhp_setup_state(CPUHP_AP_PERF_X86_IOMMU_PERF_ONLINE,
-				"driver/iommu/intel/perfmon:online",
-				iommu_pmu_cpu_online,
-				iommu_pmu_cpu_offline);
-	if (ret)
-		nr_iommu_pmu = 0;
+	ret = cpuhp_state_add_instance(iommu_cpuhp_slot, &iommu_pmu->cpuhp_node);
+	if (ret) {
+		if (!nr_iommu_pmu)
+			cpuhp_remove_multi_state(iommu_cpuhp_slot);
+		return ret;
+	}
+	nr_iommu_pmu++;
 
-	return ret;
+	return 0;
 }
 
 static void iommu_pmu_cpuhp_free(struct iommu_pmu *iommu_pmu)
 {
+	cpuhp_state_remove_instance(iommu_cpuhp_slot, &iommu_pmu->cpuhp_node);
+
 	if (--nr_iommu_pmu)
 		return;
 
-	cpuhp_remove_state(CPUHP_AP_PERF_X86_IOMMU_PERF_ONLINE);
+	cpuhp_remove_multi_state(iommu_cpuhp_slot);
 }
 
 void iommu_pmu_register(struct intel_iommu *iommu)
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index c6fab004104a..5b2f8147d1ae 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -218,7 +218,6 @@ enum cpuhp_state {
 	CPUHP_AP_PERF_X86_CQM_ONLINE,
 	CPUHP_AP_PERF_X86_CSTATE_ONLINE,
 	CPUHP_AP_PERF_X86_IDXD_ONLINE,
-	CPUHP_AP_PERF_X86_IOMMU_PERF_ONLINE,
 	CPUHP_AP_PERF_S390_CF_ONLINE,
 	CPUHP_AP_PERF_S390_SF_ONLINE,
 	CPUHP_AP_PERF_ARM_CCI_ONLINE,