PCI: hotplug: ensure a consistent return value in error case

Typically, the return value desired for the failure of a function with an
integer return value is a negative integer.  In these cases, the return
value is sometimes a negative integer and sometimes 0, due to a subsequent
initialization of the return variable within the loop.

A simplified version of the semantic match that finds this problem is:
(http://coccinelle.lip6.fr/)

//<smpl>
@r exists@
identifier ret;
position p;
constant C;
expression e1,e3,e4;
statement S;
@@

ret = -C
... when != ret = e3
    when any
if@p (...) S
... when any
if (\(ret != 0\|ret < 0\|ret > 0\) || ...) { ... return ...; }
... when != ret = e3
    when any
*if@p (...)
{
  ... when != ret = e4
  return ret;
}
//</smpl>

[bhelgaas: squashed into one patch]
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 10 insertions, 4 deletions

diff --git a/drivers/pci/hotplug/shpchp_core.c b/drivers/pci/hotplug/shpchp_core.c
index 7414fd9ad1d2..b6de307248e4 100644
--- a/drivers/pci/hotplug/shpchp_core.c
+++ b/drivers/pci/hotplug/shpchp_core.c
@@ -99,22 +99,28 @@ static int init_slots(struct controller *ctrl)
         struct hotplug_slot *hotplug_slot;
         struct hotplug_slot_info *info;
         char name[SLOT_NAME_SIZE];
-        int retval = -ENOMEM;
+        int retval;
         int i;
 
         for (i = 0; i < ctrl->num_slots; i++) {
                 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
-                if (!slot)
+                if (!slot) {
+                        retval = -ENOMEM;
                         goto error;
+                }
 
                 hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
-                if (!hotplug_slot)
+                if (!hotplug_slot) {
+                        retval = -ENOMEM;
                         goto error_slot;
+                }
                 slot->hotplug_slot = hotplug_slot;
 
                 info = kzalloc(sizeof(*info), GFP_KERNEL);
-                if (!info)
+                if (!info) {
+                        retval = -ENOMEM;
                         goto error_hpslot;
+                }
                 hotplug_slot->info = info;
 
                 slot->hp_slot = i;