[PATCH 3.4 03/37] e752x_edac: Fix pci_dev usage count

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

3.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Aristeu Rozanski <aris@redhat.com>

commit 90ed4988b8c030d65b41b7d13140e9376dc6ec5a upstream.

In case the device 0, function 1 is not found using pci_get_device(),
pci_scan_single_device() will be used but, differently than
pci_get_device(), it allocates a pci_dev but doesn't does bump the usage
count on the pci_dev and after few module removals and loads the pci_dev
will be freed.

Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Reviewed-by: mark gross <mark.gross@intel.com>
Link: http://lkml.kernel.org/r/20131205153755.GL4545@redhat.com
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/edac/e752x_edac.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/edac/e752x_edac.c
+++ b/drivers/edac/e752x_edac.c
@@ -1145,9 +1145,11 @@ static int e752x_get_devs(struct pci_dev
 	pvt->bridge_ck = pci_get_device(PCI_VENDOR_ID_INTEL,
 				pvt->dev_info->err_dev, pvt->bridge_ck);
 
-	if (pvt->bridge_ck == NULL)
+	if (pvt->bridge_ck == NULL) {
 		pvt->bridge_ck = pci_scan_single_device(pdev->bus,
 							PCI_DEVFN(0, 1));
+		pci_dev_get(pvt->bridge_ck);
+	}
 
 	if (pvt->bridge_ck == NULL) {
 		e752x_printk(KERN_ERR, "error reporting device not found:"