1 files changed, 31 insertions, 0 deletions

diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index 438c91a43508..4aaf00d2098b 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -11,6 +11,8 @@
 #include <linux/slab.h>
 #include <linux/percpu.h>
 
+#include <asm/sections.h>
+
 #include "base.h"
 
 struct devres_node {
@@ -823,6 +825,28 @@ char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp)
 EXPORT_SYMBOL_GPL(devm_kstrdup);
 
 /**
+ * devm_kstrdup_const - resource managed conditional string duplication
+ * @dev: device for which to duplicate the string
+ * @s: the string to duplicate
+ * @gfp: the GFP mask used in the kmalloc() call when allocating memory
+ *
+ * Strings allocated by devm_kstrdup_const will be automatically freed when
+ * the associated device is detached.
+ *
+ * RETURNS:
+ * Source string if it is in .rodata section otherwise it falls back to
+ * devm_kstrdup.
+ */
+const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp)
+{
+        if (is_kernel_rodata((unsigned long)s))
+                return s;
+
+        return devm_kstrdup(dev, s, gfp);
+}
+EXPORT_SYMBOL_GPL(devm_kstrdup_const);
+
+/**
  * devm_kvasprintf - Allocate resource managed space and format a string
  *                   into that.
  * @dev: Device to allocate memory for
@@ -889,6 +913,13 @@ void devm_kfree(struct device *dev, const void *p)
 {
         int rc;
 
+        /*
+         * Special case: pointer to a string in .rodata returned by
+         * devm_kstrdup_const().
+         */
+        if (unlikely(is_kernel_rodata((unsigned long)p)))
+                return;
+
         rc = devres_destroy(dev, devm_kmalloc_release,
                             devm_kmalloc_match, (void *)p);
         WARN_ON(rc);