i5400_edac: Avoid calling pci_put_device() twice

When i5400_edac driver is removed and re-loaded a few times, it causes
an OOPS, as it is currently decrementing some PCI device usage two
times.

When called inside a loop, pci_get_device() will call
pci_put_device(). That mangles the error count. In this specific
case, it seems easier to just duplicate the call.

Also fixes the error logic when pci_get_device fails.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 38 insertions, 16 deletions

diff --git a/drivers/edac/i5400_edac.c b/drivers/edac/i5400_edac.c
index 74d6ec342afb..b44a5de1c22c 100644
--- a/drivers/edac/i5400_edac.c
+++ b/drivers/edac/i5400_edac.c
@@ -735,7 +735,7 @@ static int i5400_get_devices(struct mem_ctl_info *mci, int dev_idx)
 
         /* Attempt to 'get' the MCH register we want */
         pdev = NULL;
-        while (!pvt->branchmap_werrors || !pvt->fsb_error_regs) {
+        while (1) {
                 pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
                                       PCI_DEVICE_ID_INTEL_5400_ERR, pdev);
                 if (!pdev) {
@@ -743,23 +743,42 @@ static int i5400_get_devices(struct mem_ctl_info *mci, int dev_idx)
                         i5400_printk(KERN_ERR,
                                 "'system address,Process Bus' "
                                 "device not found:"
-                                "vendor 0x%x device 0x%x ERR funcs "
+                                "vendor 0x%x device 0x%x ERR func 1 "
                                 "(broken BIOS?)\n",
                                 PCI_VENDOR_ID_INTEL,
                                 PCI_DEVICE_ID_INTEL_5400_ERR);
-                        goto error;
+                        return -ENODEV;
                 }
 
-                /* Store device 16 funcs 1 and 2 */
-                switch (PCI_FUNC(pdev->devfn)) {
-                case 1:
-                        pvt->branchmap_werrors = pdev;
-                        break;
-                case 2:
-                        pvt->fsb_error_regs = pdev;
+                /* Store device 16 func 1 */
+                if (PCI_FUNC(pdev->devfn) == 1)
                         break;
+        }
+        pvt->branchmap_werrors = pdev;
+
+        pdev = NULL;
+        while (1) {
+                pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
+                                      PCI_DEVICE_ID_INTEL_5400_ERR, pdev);
+                if (!pdev) {
+                        /* End of list, leave */
+                        i5400_printk(KERN_ERR,
+                                "'system address,Process Bus' "
+                                "device not found:"
+                                "vendor 0x%x device 0x%x ERR func 2 "
+                                "(broken BIOS?)\n",
+                                PCI_VENDOR_ID_INTEL,
+                                PCI_DEVICE_ID_INTEL_5400_ERR);
+
+                        pci_dev_put(pvt->branchmap_werrors);
+                        return -ENODEV;
                 }
+
+                /* Store device 16 func 2 */
+                if (PCI_FUNC(pdev->devfn) == 2)
+                        break;
         }
+        pvt->fsb_error_regs = pdev;
 
         debugf1("System Address, processor bus- PCI Bus ID: %s  %x:%x\n",
                 pci_name(pvt->system_address),
@@ -778,7 +797,10 @@ static int i5400_get_devices(struct mem_ctl_info *mci, int dev_idx)
                         "MC: 'BRANCH 0' device not found:"
                         "vendor 0x%x device 0x%x Func 0 (broken BIOS?)\n",
                         PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5400_FBD0);
-                goto error;
+
+                pci_dev_put(pvt->fsb_error_regs);
+                pci_dev_put(pvt->branchmap_werrors);
+                return -ENODEV;
         }
 
         /* If this device claims to have more than 2 channels then
@@ -796,14 +818,14 @@ static int i5400_get_devices(struct mem_ctl_info *mci, int dev_idx)
                         "(broken BIOS?)\n",
                         PCI_VENDOR_ID_INTEL,
                         PCI_DEVICE_ID_INTEL_5400_FBD1);
-                goto error;
+
+                pci_dev_put(pvt->branch_0);
+                pci_dev_put(pvt->fsb_error_regs);
+                pci_dev_put(pvt->branchmap_werrors);
+                return -ENODEV;
         }
 
         return 0;
-
-error:
-        i5400_put_devices(mci);
-        return -ENODEV;
 }
 
 /*