7 files changed, 77 insertions, 26 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 9e06b7f5ecf1..1b4afd2e6ca0 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -994,13 +994,16 @@ config FAULT_INJECTION_STACKTRACE_FILTER
 
 config LATENCYTOP
         bool "Latency measuring infrastructure"
+        depends on HAVE_LATENCYTOP_SUPPORT
+        depends on DEBUG_KERNEL
+        depends on STACKTRACE_SUPPORT
+        depends on PROC_FS
         select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE
         select KALLSYMS
         select KALLSYMS_ALL
         select STACKTRACE
         select SCHEDSTATS
         select SCHED_DEBUG
-        depends on HAVE_LATENCYTOP_SUPPORT
         help
           Enable this option if you want to use the LatencyTOP tool
           to find out which userspace is blocking on what kernel operations.
diff --git a/lib/bug.c b/lib/bug.c
index 7cdfad88128f..19552096d16b 100644
--- a/lib/bug.c
+++ b/lib/bug.c
@@ -72,8 +72,8 @@ static const struct bug_entry *module_find_bug(unsigned long bugaddr)
         return NULL;
 }
 
-int module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
-                        struct module *mod)
+void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
+                         struct module *mod)
 {
         char *secstrings;
         unsigned int i;
@@ -97,8 +97,6 @@ int module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
          * could potentially lead to deadlock and thus be counter-productive.
          */
         list_add(&mod->bug_list, &module_bug_list);
-
-        return 0;
 }
 
 void module_bug_cleanup(struct module *mod)
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index b93579504dfa..70af0a7f97c0 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -123,7 +123,7 @@ static int kobj_usermode_filter(struct kobject *kobj)
  * @kobj: struct kobject that the action is happening to
  * @envp_ext: pointer to environmental data
  *
- * Returns 0 if kobject_uevent() is completed with success or the
+ * Returns 0 if kobject_uevent_env() is completed with success or the
  * corresponding error when it fails.
  */
 int kobject_uevent_env(struct kobject *kobj, enum kobject_action action,
@@ -317,7 +317,7 @@ exit:
 EXPORT_SYMBOL_GPL(kobject_uevent_env);
 
 /**
- * kobject_uevent - notify userspace by ending an uevent
+ * kobject_uevent - notify userspace by sending an uevent
  *
  * @action: action that is happening
  * @kobj: struct kobject that the action is happening to
diff --git a/lib/list_sort.c b/lib/list_sort.c
index 4b5cb794c38b..a7616fa3162e 100644
--- a/lib/list_sort.c
+++ b/lib/list_sort.c
@@ -70,7 +70,7 @@ static void merge_and_restore_back_links(void *priv,
                  * element comparison is needed, so the client's cmp()
                  * routine can invoke cond_resched() periodically.
                  */
-                (*cmp)(priv, tail, tail);
+                (*cmp)(priv, tail->next, tail->next);
 
                 tail->next->prev = tail;
                 tail = tail->next;
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index e907858498a6..efd16fa80b1c 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -174,14 +174,16 @@ static void radix_tree_node_rcu_free(struct rcu_head *head)
 {
         struct radix_tree_node *node =
                         container_of(head, struct radix_tree_node, rcu_head);
+        int i;
 
         /*
          * must only free zeroed nodes into the slab. radix_tree_shrink
          * can leave us with a non-NULL entry in the first slot, so clear
          * that here to make sure.
          */
-        tag_clear(node, 0, 0);
-        tag_clear(node, 1, 0);
+        for (i = 0; i < RADIX_TREE_MAX_TAGS; i++)
+                tag_clear(node, i, 0);
+
         node->slots[0] = NULL;
         node->count = 0;
 
@@ -623,17 +625,30 @@ EXPORT_SYMBOL(radix_tree_tag_get);
  * also settag. The function stops either after tagging nr_to_tag items or
  * after reaching last_index.
  *
+ * The tags must be set from the leaf level only and propagated back up the
+ * path to the root. We must do this so that we resolve the full path before
+ * setting any tags on intermediate nodes. If we set tags as we descend, then
+ * we can get to the leaf node and find that the index that has the iftag
+ * set is outside the range we are scanning. This reults in dangling tags and
+ * can lead to problems with later tag operations (e.g. livelocks on lookups).
+ *
  * The function returns number of leaves where the tag was set and sets
  * *first_indexp to the first unscanned index.
+ * WARNING! *first_indexp can wrap if last_index is ULONG_MAX. Caller must
+ * be prepared to handle that.
  */
 unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root,
                 unsigned long *first_indexp, unsigned long last_index,
                 unsigned long nr_to_tag,
                 unsigned int iftag, unsigned int settag)
 {
-        unsigned int height = root->height, shift;
-        unsigned long tagged = 0, index = *first_indexp;
-        struct radix_tree_node *open_slots[height], *slot;
+        unsigned int height = root->height;
+        struct radix_tree_path path[height];
+        struct radix_tree_path *pathp = path;
+        struct radix_tree_node *slot;
+        unsigned int shift;
+        unsigned long tagged = 0;
+        unsigned long index = *first_indexp;
 
         last_index = min(last_index, radix_tree_maxindex(height));
         if (index > last_index)
@@ -653,6 +668,13 @@ unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root,
         shift = (height - 1) * RADIX_TREE_MAP_SHIFT;
         slot = radix_tree_indirect_to_ptr(root->rnode);
 
+        /*
+         * we fill the path from (root->height - 2) to 0, leaving the index at
+         * (root->height - 1) as a terminator. Zero the node in the terminator
+         * so that we can use this to end walk loops back up the path.
+         */
+        path[height - 1].node = NULL;
+
         for (;;) {
                 int offset;
 
@@ -661,21 +683,35 @@ unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root,
                         goto next;
                 if (!tag_get(slot, iftag, offset))
                         goto next;
+                if (height > 1) {
+                        /* Go down one level */
+                        height--;
+                        shift -= RADIX_TREE_MAP_SHIFT;
+                        path[height - 1].node = slot;
+                        path[height - 1].offset = offset;
+                        slot = slot->slots[offset];
+                        continue;
+                }
+
+                /* tag the leaf */
+                tagged++;
                 tag_set(slot, settag, offset);
-                if (height == 1) {
-                        tagged++;
-                        goto next;
+
+                /* walk back up the path tagging interior nodes */
+                pathp = &path[0];
+                while (pathp->node) {
+                        /* stop if we find a node with the tag already set */
+                        if (tag_get(pathp->node, settag, pathp->offset))
+                                break;
+                        tag_set(pathp->node, settag, pathp->offset);
+                        pathp++;
                 }
-                /* Go down one level */
-                height--;
-                shift -= RADIX_TREE_MAP_SHIFT;
-                open_slots[height] = slot;
-                slot = slot->slots[offset];
-                continue;
+
 next:
                 /* Go to next item at level determined by 'shift' */
                 index = ((index >> shift) + 1) << shift;
-                if (index > last_index)
+                /* Overflow can happen when last_index is ~0UL... */
+                if (index > last_index || !index)
                         break;
                 if (tagged >= nr_to_tag)
                         break;
@@ -685,7 +721,7 @@ next:
                          * last_index is guaranteed to be in the tree, what
                          * we do below cannot wander astray.
                          */
-                        slot = open_slots[height];
+                        slot = path[height - 1].node;
                         height++;
                         shift += RADIX_TREE_MAP_SHIFT;
                 }
diff --git a/lib/raid6/.gitignore b/lib/raid6/.gitignore
new file mode 100644
index 000000000000..162becacf97c
--- /dev/null
+++ b/lib/raid6/.gitignore
@@ -0,0 +1,4 @@
+mktables
+altivec*.c
+int*.c
+tables.c
diff --git a/lib/scatterlist.c b/lib/scatterlist.c
index a5ec42868f99..4ceb05d772ae 100644
--- a/lib/scatterlist.c
+++ b/lib/scatterlist.c
@@ -248,8 +248,18 @@ int __sg_alloc_table(struct sg_table *table, unsigned int nents,
                 left -= sg_size;
 
                 sg = alloc_fn(alloc_size, gfp_mask);
-                if (unlikely(!sg))
-                        return -ENOMEM;
+                if (unlikely(!sg)) {
+                        /*
+                         * Adjust entry count to reflect that the last
+                         * entry of the previous table won't be used for
+                         * linkage.  Without this, sg_kfree() may get
+                         * confused.
+                         */
+                        if (prv)
+                                table->nents = ++table->orig_nents;
+
+                        return -ENOMEM;
+                }
 
                 sg_init_table(sg, alloc_size);
                 table->nents = table->orig_nents += sg_size;