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/cpqphp_core.c b/drivers/pci/hotplug/cpqphp_core.c
index 187a199da93c..c8eaeb43fa5d 100644
--- a/drivers/pci/hotplug/cpqphp_core.c
+++ b/drivers/pci/hotplug/cpqphp_core.c
@@ -611,7 +611,7 @@ static int ctrl_slot_setup(struct controller *ctrl,
 	u32 tempdword;
 	char name[SLOT_NAME_SIZE];
 	void __iomem *slot_entry= NULL;
-	int result = -ENOMEM;
+	int result;
 
 	dbg("%s\n", __func__);
 
@@ -623,19 +623,25 @@ static int ctrl_slot_setup(struct controller *ctrl,
 
 	while (number_of_slots) {
 		slot = kzalloc(sizeof(*slot), GFP_KERNEL);
-		if (!slot)
+		if (!slot) {
+			result = -ENOMEM;
 			goto error;
+		}
 
 		slot->hotplug_slot = kzalloc(sizeof(*(slot->hotplug_slot)),
 						GFP_KERNEL);
-		if (!slot->hotplug_slot)
+		if (!slot->hotplug_slot) {
+			result = -ENOMEM;
 			goto error_slot;
+		}
 		hotplug_slot = slot->hotplug_slot;
 
 		hotplug_slot->info = kzalloc(sizeof(*(hotplug_slot->info)),
 							GFP_KERNEL);
-		if (!hotplug_slot->info)
+		if (!hotplug_slot->info) {
+			result = -ENOMEM;
 			goto error_hpslot;
+		}
 		hotplug_slot_info = hotplug_slot->info;
 
 		slot->ctrl = ctrl;