Merge tag 'iommu-fixes-v5.15-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull iommu fixes from Joerg Roedel:

 - Intel VT-d:
     - PASID leakage in intel_svm_unbind_mm()
     - Deadlock in intel_svm_drain_prq()

 - AMD IOMMU: Fixes for an unhandled page-fault bug when AVIC is used
   for a KVM guest.

 - Make CONFIG_IOMMU_DEFAULT_DMA_LAZY architecture instead of IOMMU
   driver dependent

* tag 'iommu-fixes-v5.15-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu: Clarify default domain Kconfig
  iommu/vt-d: Fix a deadlock in intel_svm_drain_prq()
  iommu/vt-d: Fix PASID leak in intel_svm_unbind_mm()
  iommu/amd: Remove iommu_init_ga()
  iommu/amd: Relocate GAMSup check to early_enable_iommus

Author: torvalds

drivers/iommu/Kconfig

@@ -82,7 +82,7 @@ config IOMMU_DEBUGFS
 choice
 	prompt "IOMMU default domain type"
 	depends on IOMMU_API
-	default IOMMU_DEFAULT_DMA_LAZY if AMD_IOMMU || INTEL_IOMMU
+	default IOMMU_DEFAULT_DMA_LAZY if X86 || IA64
 	default IOMMU_DEFAULT_DMA_STRICT
 	help
 	  Choose the type of IOMMU domain used to manage DMA API usage by

drivers/iommu/amd/init.c

@@ -297,6 +297,22 @@ int amd_iommu_get_num_iommus(void)
 	return amd_iommus_present;
 }
 
+#ifdef CONFIG_IRQ_REMAP
+static bool check_feature_on_all_iommus(u64 mask)
+{
+	bool ret = false;
+	struct amd_iommu *iommu;
+
+	for_each_iommu(iommu) {
+		ret = iommu_feature(iommu, mask);
+		if (!ret)
+			return false;
+	}
+
+	return true;
+}
+#endif
+
 /*
  * For IVHD type 0x11/0x40, EFR is also available via IVHD.
  * Default to IVHD EFR since it is available sooner
@@ -813,9 +829,9 @@ static int iommu_ga_log_enable(struct amd_iommu *iommu)
 	return 0;
 }
 
-#ifdef CONFIG_IRQ_REMAP
 static int iommu_init_ga_log(struct amd_iommu *iommu)
 {
+#ifdef CONFIG_IRQ_REMAP
 	u64 entry;
 
 	if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))
@@ -845,25 +861,9 @@ static int iommu_init_ga_log(struct amd_iommu *iommu)
 err_out:
 	free_ga_log(iommu);
 	return -EINVAL;
-}
-#endif /* CONFIG_IRQ_REMAP */
-
-static int iommu_init_ga(struct amd_iommu *iommu)
-{
-	int ret = 0;
-
-#ifdef CONFIG_IRQ_REMAP
-	/* Note: We have already checked GASup from IVRS table.
-	 *       Now, we need to make sure that GAMSup is set.
-	 */
-	if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) &&
-	    !iommu_feature(iommu, FEATURE_GAM_VAPIC))
-		amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY_GA;
-
-	ret = iommu_init_ga_log(iommu);
+#else
+	return 0;
 #endif /* CONFIG_IRQ_REMAP */
-
-	return ret;
 }
 
 static int __init alloc_cwwb_sem(struct amd_iommu *iommu)
@@ -1845,7 +1845,7 @@ static int __init iommu_init_pci(struct amd_iommu *iommu)
 	if (iommu_feature(iommu, FEATURE_PPR) && alloc_ppr_log(iommu))
 		return -ENOMEM;
 
-	ret = iommu_init_ga(iommu);
+	ret = iommu_init_ga_log(iommu);
 	if (ret)
 		return ret;
 
@@ -2479,6 +2479,14 @@ static void early_enable_iommus(void)
 	}
 
 #ifdef CONFIG_IRQ_REMAP
+	/*
+	 * Note: We have already checked GASup from IVRS table.
+	 *       Now, we need to make sure that GAMSup is set.
+	 */
+	if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) &&
+	    !check_feature_on_all_iommus(FEATURE_GAM_VAPIC))
+		amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY_GA;
+
 	if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))
 		amd_iommu_irq_ops.capability |= (1 << IRQ_POSTING_CAP);
 #endif

drivers/iommu/intel/svm.c

@@ -514,9 +514,6 @@ static void load_pasid(struct mm_struct *mm, u32 pasid)
 {
 	mutex_lock(&mm->context.lock);
 
-	/* Synchronize with READ_ONCE in update_pasid(). */
-	smp_store_release(&mm->pasid, pasid);
-
 	/* Update PASID MSR on all CPUs running the mm's tasks. */
 	on_each_cpu_mask(mm_cpumask(mm), _load_pasid, NULL, true);
 
@@ -792,7 +789,19 @@ static void intel_svm_drain_prq(struct device *dev, u32 pasid)
 		goto prq_retry;
 	}
 
+	/*
+	 * A work in IO page fault workqueue may try to lock pasid_mutex now.
+	 * Holding pasid_mutex while waiting in iopf_queue_flush_dev() for
+	 * all works in the workqueue to finish may cause deadlock.
+	 *
+	 * It's unnecessary to hold pasid_mutex in iopf_queue_flush_dev().
+	 * Unlock it to allow the works to be handled while waiting for
+	 * them to finish.
+	 */
+	lockdep_assert_held(&pasid_mutex);
+	mutex_unlock(&pasid_mutex);
 	iopf_queue_flush_dev(dev);
+	mutex_lock(&pasid_mutex);
 
 	/*
 	 * Perform steps described in VT-d spec CH7.10 to drain page