devm_memremap: Fix error value when memremap failed

devm_memremap() returns an ERR_PTR() value in case of error.
However, it returns NULL when memremap() failed.  This causes
the caller, such as the pmem driver, to proceed and oops later.

Change devm_memremap() to return ERR_PTR(-ENXIO) when memremap()
failed.

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 2c468dea60bc..b04ea2f5fbfe 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -136,8 +136,10 @@ void *devm_memremap(struct device *dev, resource_size_t offset,
         if (addr) {
                 *ptr = addr;
                 devres_add(dev, ptr);
-        } else
+        } else {
                 devres_free(ptr);
+                return ERR_PTR(-ENXIO);
+        }
 
         return addr;
 }