Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Ingo Molnar:
 "A sparse irq race/locking fix, and a MSI irq domains population fix"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq: Make sparse_irq_lock protect what it should protect
  genirq/msi: Fix populating multiple interrupts

2 files changed, 10 insertions, 19 deletions

diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 73be2b3909bd..82afb7ed369f 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -421,10 +421,8 @@ static void free_desc(unsigned int irq)
          * The sysfs entry must be serialized against a concurrent
          * irq_sysfs_init() as well.
          */
-        mutex_lock(&sparse_irq_lock);
         kobject_del(&desc->kobj);
         delete_irq_desc(irq);
-        mutex_unlock(&sparse_irq_lock);
 
         /*
          * We free the descriptor, masks and stat fields via RCU. That
@@ -462,20 +460,15 @@ static int alloc_descs(unsigned int start, unsigned int cnt, int node,
                 desc = alloc_desc(start + i, node, flags, mask, owner);
                 if (!desc)
                         goto err;
-                mutex_lock(&sparse_irq_lock);
                 irq_insert_desc(start + i, desc);
                 irq_sysfs_add(start + i, desc);
-                mutex_unlock(&sparse_irq_lock);
         }
+        bitmap_set(allocated_irqs, start, cnt);
         return start;
 
 err:
         for (i--; i >= 0; i--)
                 free_desc(start + i);
-
-        mutex_lock(&sparse_irq_lock);
-        bitmap_clear(allocated_irqs, start, cnt);
-        mutex_unlock(&sparse_irq_lock);
         return -ENOMEM;
 }
 
@@ -575,6 +568,7 @@ static inline int alloc_descs(unsigned int start, unsigned int cnt, int node,
 
                 desc->owner = owner;
         }
+        bitmap_set(allocated_irqs, start, cnt);
         return start;
 }
 
@@ -670,10 +664,10 @@ void irq_free_descs(unsigned int from, unsigned int cnt)
         if (from >= nr_irqs || (from + cnt) > nr_irqs)
                 return;
 
+        mutex_lock(&sparse_irq_lock);
         for (i = 0; i < cnt; i++)
                 free_desc(from + i);
 
-        mutex_lock(&sparse_irq_lock);
         bitmap_clear(allocated_irqs, from, cnt);
         mutex_unlock(&sparse_irq_lock);
 }
@@ -720,19 +714,15 @@ __irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node,
                                            from, cnt, 0);
         ret = -EEXIST;
         if (irq >=0 && start != irq)
-                goto err;
+                goto unlock;
 
         if (start + cnt > nr_irqs) {
                 ret = irq_expand_nr_irqs(start + cnt);
                 if (ret)
-                        goto err;
+                        goto unlock;
         }
-
-        bitmap_set(allocated_irqs, start, cnt);
-        mutex_unlock(&sparse_irq_lock);
-        return alloc_descs(start, cnt, node, affinity, owner);
-
-err:
+        ret = alloc_descs(start, cnt, node, affinity, owner);
+unlock:
         mutex_unlock(&sparse_irq_lock);
         return ret;
 }
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index 48eadf416c24..3fa4bd59f569 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -315,11 +315,12 @@ int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
 
                 ops->set_desc(arg, desc);
                 /* Assumes the domain mutex is held! */
-                ret = irq_domain_alloc_irqs_hierarchy(domain, virq, 1, arg);
+                ret = irq_domain_alloc_irqs_hierarchy(domain, desc->irq, 1,
+                                                      arg);
                 if (ret)
                         break;
 
-                irq_set_msi_desc_off(virq, 0, desc);
+                irq_set_msi_desc_off(desc->irq, 0, desc);
         }
 
         if (ret) {