The following directory structure will allow for cases when the same
function name exists in a single object.
        /sys/kernel/livepatch/<patch>/<object>/<function.number>

The number is incremented on each known initialized func kobj thus creating
unique names in this case.

An example of this issue is documented here:
        https://github.com/dynup/kpatch/issues/493

Signed-off-by: Chris J Arges <chris.j.ar...@canonical.com>
---
 Documentation/ABI/testing/sysfs-kernel-livepatch |  2 +-
 kernel/livepatch/core.c                          | 20 ++++++++++++++++++--
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-kernel-livepatch 
b/Documentation/ABI/testing/sysfs-kernel-livepatch
index 5bf42a8..dcd36db 100644
--- a/Documentation/ABI/testing/sysfs-kernel-livepatch
+++ b/Documentation/ABI/testing/sysfs-kernel-livepatch
@@ -33,7 +33,7 @@ Description:
                The object directory contains subdirectories for each function
                that is patched within the object.
 
-What:          /sys/kernel/livepatch/<patch>/<object>/<function>
+What:          /sys/kernel/livepatch/<patch>/<object>/<function.number>
 Date:          Nov 2014
 KernelVersion: 3.19.0
 Contact:       live-patch...@vger.kernel.org
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index 6e53441..ecacf65 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -587,7 +587,7 @@ EXPORT_SYMBOL_GPL(klp_enable_patch);
  * /sys/kernel/livepatch/<patch>
  * /sys/kernel/livepatch/<patch>/enabled
  * /sys/kernel/livepatch/<patch>/<object>
- * /sys/kernel/livepatch/<patch>/<object>/<func>
+ * /sys/kernel/livepatch/<patch>/<object>/<func.number>
  */
 
 static ssize_t enabled_store(struct kobject *kobj, struct kobj_attribute *attr,
@@ -727,13 +727,29 @@ static void klp_free_patch(struct klp_patch *patch)
        kobject_put(&patch->kobj);
 }
 
+static int klp_count_sysfs_funcs(struct klp_object *obj, const char *name)
+{
+       struct klp_func *func;
+       int n = 0;
+
+       /* count the times a function name occurs and is initialized */
+       klp_for_each_func(obj, func) {
+               if ((!strcmp(func->old_name, name) &&
+                   func->kobj.state_initialized))
+                       n++;
+       }
+
+       return n;
+}
+
 static int klp_init_func(struct klp_object *obj, struct klp_func *func)
 {
        INIT_LIST_HEAD(&func->stack_node);
        func->state = KLP_DISABLED;
 
        return kobject_init_and_add(&func->kobj, &klp_ktype_func,
-                                   &obj->kobj, "%s", func->old_name);
+                                   &obj->kobj, "%s.%d", func->old_name,
+                                   klp_count_sysfs_funcs(obj, func->old_name));
 }
 
 /* parts of the initialization that is done only when the object is loaded */
-- 
1.9.1

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