From 8108de9739abeec72f4811532109695e245df42a Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Tue, 6 Nov 2012 15:04:44 -0700 Subject: [PATCH] [SCSI] gdth: Remove buggy ROM handling The ROM address handling in gdth_init_pci() is useless and possibly dangerous. This patch removes it. "pci_resource_start(pdev, 8)" is not well-defined. PCI resources 0-5 are standard PCI BARs and 6 is the expansion ROM. Resource 8 is either an SR-IOV BAR (if CONFIG_PCI_IOV=y, resources 7-12 are SR-IOV BARs) or a bridge window (resources 7-10). The GDT device is neither an SR-IOV device nor a bridge, so in either case resource 8 should be zero since struct pci_dev is allocated with kzalloc(). It is illegal for a driver to write an arbitrary address to the ROM BAR because it has no way of knowing whether the ROM will conflict with another device. I think the only effect of the code being removed was to: 1) Enable the ROM at 0xFEFF0000 (possibly causing a conflict with another device) 2) Delay one millisecond 3) Write zero to the ROM BAR, disabling it I doubt the delay is needed, but I left it since it seems innocuous. Signed-off-by: Bjorn Helgaas Signed-off-by: James Bottomley --- drivers/scsi/gdth.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/gdth.c b/drivers/scsi/gdth.c index 599790e41a98..59bceac51a4c 100644 --- a/drivers/scsi/gdth.c +++ b/drivers/scsi/gdth.c @@ -1107,14 +1107,8 @@ static int gdth_init_pci(struct pci_dev *pdev, gdth_pci_str *pcistr, pci_read_config_word(pdev, PCI_COMMAND, &command); command |= 6; pci_write_config_word(pdev, PCI_COMMAND, command); - if (pci_resource_start(pdev, 8) == 1UL) - pci_resource_start(pdev, 8) = 0UL; - i = 0xFEFF0001UL; - pci_write_config_dword(pdev, PCI_ROM_ADDRESS, i); - gdth_delay(1); - pci_write_config_dword(pdev, PCI_ROM_ADDRESS, - pci_resource_start(pdev, 8)); - + gdth_delay(1); + dp6m_ptr = ha->brd; /* Ensure that it is safe to access the non HW portions of DPMEM. -- GitLab