PCI: Skip id checking if no id is passed

Will get warning when pci stub driver is built-in kenel like:
pci-stub: invalid id string ""

So stop early if no id is passed.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/pci/pci-stub.c b/drivers/pci/pci-stub.c
index f7b68ca6cc98..4c0336b31caf 100644
--- a/drivers/pci/pci-stub.c
+++ b/drivers/pci/pci-stub.c
@@ -47,6 +47,10 @@ static int __init pci_stub_init(void)
         if (rc)
                 return rc;
 
+        /* no ids passed actually */
+        if (ids[0] == '\0')
+                return 0;
+
         /* add ids specified in the module parameter */
         p = ids;
         while ((id = strsep(&p, ","))) {