redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

i7300_edac: Fix device reference count 

pci_get_device() decrements the reference count of "from" (last
argument) so when we break off the loop successfully we have only one
device reference - and we don't know which device we have. If we want
a reference to each device, we must take them explicitly and let
the pci_get_device() walk complete to avoid duplicate references.

This is serious, as over-putting device references will cause
the device to eventually disappear. Without this fix, the kernel
crashes after a few insmod/rmmod cycles.

Tested on an Intel S7000FC4UR system with a 7300 chipset.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Link: http://lkml.kernel.org/r/20140224111656.09bbb7ed@endymion.delvare
Cc: Mauro Carvalho Chehab <m.chehab@samsung.com>
Cc: Doug Thompson <dougthompson@xmission.com>
Cc: stable@vger.kernel.org
Signed-off-by: Borislav Petkov <bp@suse.de>
hifive-unleashed-5.1
Jean Delvare 2014-02-25 09:43:13 +01:00 committed by Borislav Petkov
parent c0f5eeed0f
commit 75135da0d6
1 changed files with 20 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
drivers/edac/i7300_edac.c
View File

@ -943,33 +943,35 @@ static int i7300_get_devices(struct mem_ctl_info *mci)
/* Attempt to 'get' the MCH register we want */
pdev = NULL;
while (!pvt->pci_dev_16_1_fsb_addr_map ||
!pvt->pci_dev_16_2_fsb_err_regs) {
pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
PCI_DEVICE_ID_INTEL_I7300_MCH_ERR, pdev);
if (!pdev) {
/* End of list, leave */
i7300_printk(KERN_ERR,
"'system address,Process Bus' "
"device not found:"
"vendor 0x%x device 0x%x ERR funcs "
"(broken BIOS?)\n",
PCI_VENDOR_ID_INTEL,
PCI_DEVICE_ID_INTEL_I7300_MCH_ERR);
goto error;
}
while ((pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
PCI_DEVICE_ID_INTEL_I7300_MCH_ERR,
pdev))) {
/* Store device 16 funcs 1 and 2 */
switch (PCI_FUNC(pdev->devfn)) {
case 1:
pvt->pci_dev_16_1_fsb_addr_map = pdev;
if (!pvt->pci_dev_16_1_fsb_addr_map)
pvt->pci_dev_16_1_fsb_addr_map =
pci_dev_get(pdev);
break;
case 2:
pvt->pci_dev_16_2_fsb_err_regs = pdev;
if (!pvt->pci_dev_16_2_fsb_err_regs)
pvt->pci_dev_16_2_fsb_err_regs =
pci_dev_get(pdev);
break;
}
}
if (!pvt->pci_dev_16_1_fsb_addr_map ||
!pvt->pci_dev_16_2_fsb_err_regs) {
/* At least one device was not found */
i7300_printk(KERN_ERR,
"'system address,Process Bus' device not found:"
"vendor 0x%x device 0x%x ERR funcs (broken BIOS?)\n",
PCI_VENDOR_ID_INTEL,
PCI_DEVICE_ID_INTEL_I7300_MCH_ERR);
goto error;
}
edac_dbg(1, "System Address, processor bus- PCI Bus ID: %s %x:%x\n",
pci_name(pvt->pci_dev_16_0_fsb_ctlr),
pvt->pci_dev_16_0_fsb_ctlr->vendor,