PCI: for address space collisions, show conflicting resource

With request_resource_conflict(), we can learn what the actual conflict is,
so print that info for debugging purposes.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 8 insertions, 6 deletions

diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c
index 7d678bb15ffb..17bed18d24ad 100644
--- a/drivers/pci/setup-res.c
+++ b/drivers/pci/setup-res.c
@@ -93,8 +93,7 @@ void pci_update_resource(struct pci_dev *dev, int resno)
 int pci_claim_resource(struct pci_dev *dev, int resource)
 {
         struct resource *res = &dev->resource[resource];
-        struct resource *root;
-        int err;
+        struct resource *root, *conflict;
 
         root = pci_find_parent_resource(dev, res);
         if (!root) {
@@ -103,12 +102,15 @@ int pci_claim_resource(struct pci_dev *dev, int resource)
                 return -EINVAL;
         }
 
-        err = request_resource(root, res);
-        if (err)
+        conflict = request_resource_conflict(root, res);
+        if (conflict) {
                 dev_err(&dev->dev,
-                        "address space collision: %pR already in use\n", res);
+                        "address space collision: %pR conflicts with %s %pR\n",
+                        res, conflict->name, conflict);
+                return -EBUSY;
+        }
 
-        return err;
+        return 0;
 }
 EXPORT_SYMBOL(pci_claim_resource);