[PATCH] i5400_edac: Avoid calling pci_put_device() twice

From: Mauro Carvalho Chehab
Date: Wed Mar 07 2012 - 06:36:13 EST


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@xxxxxxxxxx>
---
drivers/edac/i5400_edac.c | 54 +++++++++++++++++++++++++++++++-------------
1 files changed, 38 insertions(+), 16 deletions(-)

diff --git a/drivers/edac/i5400_edac.c b/drivers/edac/i5400_edac.c
index 74d6ec34..b44a5de 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;
}

/*
--
1.7.8

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