Merge tag 'iommu-updates-v3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull IOMMU updates from Joerg Roedel:
 "Not much stuff this time.  The only change to the IOMMU core code is
  the addition of a handle to the fault handling code.  A few updates to
  the AMD IOMMU driver to work around new errata.  The other patches are
  mostly fixes and enhancements to the existing ARM IOMMU drivers and
  documentation updates.

  A new IOMMU driver for the Exynos platform was also underway but got
  merged via the Samsung tree and is not part of this tree."

* tag 'iommu-updates-v3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  Documentation: kernel-parameters.txt Add amd_iommu_dump
  iommu/core: pass a user-provided token to fault handlers
  iommu/tegra: gart: Fix register offset correctly
  iommu: OMAP: device detach on domain destroy
  iommu: tegra/gart: Add device tree support
  iommu: tegra/gart: use correct gart_device
  iommu/tegra: smmu: Print device name correctly
  iommu/amd: Add workaround for event log erratum
  iommu/amd: Check for the right TLP prefix bit
  dma-debug: release free_entries_lock before saving stack trace

lib/dma-debug.c

@@ -430,7 +430,7 @@ static struct dma_debug_entry *__dma_entry_alloc(void)
  */
 static struct dma_debug_entry *dma_entry_alloc(void)
 {
-	struct dma_debug_entry *entry = NULL;
+	struct dma_debug_entry *entry;
 	unsigned long flags;
 
 	spin_lock_irqsave(&free_entries_lock, flags);
@@ -438,11 +438,14 @@ static struct dma_debug_entry *dma_entry_alloc(void)
 	if (list_empty(&free_entries)) {
 		pr_err("DMA-API: debugging out of memory - disabling\n");
 		global_disable = true;
-		goto out;
+		spin_unlock_irqrestore(&free_entries_lock, flags);
+		return NULL;
 	}
 
 	entry = __dma_entry_alloc();
 
+	spin_unlock_irqrestore(&free_entries_lock, flags);
+
 #ifdef CONFIG_STACKTRACE
 	entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES;
 	entry->stacktrace.entries = entry->st_entries;
@@ -450,9 +453,6 @@ static struct dma_debug_entry *dma_entry_alloc(void)
 	save_stack_trace(&entry->stacktrace);
 #endif
 
-out:
-	spin_unlock_irqrestore(&free_entries_lock, flags);
-
 	return entry;
 }