diff options
| author | Naveen Naidu <naveennaidu479@gmail.com> | 2021-11-18 15:03:26 +0100 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2021-11-18 21:12:57 +0100 |
| commit | fa52b6447ce1cc0157c89dac7762f1693deeb10e (patch) | |
| tree | 21b89ed676e47cf141e603a574372634add9edfd /drivers/pci/probe.c | |
| parent | PCI: rockchip-host: Drop error data fabrication when config read fails (diff) | |
| download | linux-fa52b6447ce1cc0157c89dac7762f1693deeb10e.tar.xz linux-fa52b6447ce1cc0157c89dac7762f1693deeb10e.zip | |
PCI/ERR: Use PCI_POSSIBLE_ERROR() to check config reads
When config pci_ops.read() can detect failed PCI transactions, the data
returned to the CPU is PCI_ERROR_RESPONSE (~0 or 0xffffffff).
Obviously a successful PCI config read may *also* return that data if a
config register happens to contain ~0, so it doesn't definitively indicate
an error unless we know the register cannot contain ~0.
Use PCI_POSSIBLE_ERROR() to check the response we get when we read data
from hardware. This unifies PCI error response checking and makes error
checks consistent and easier to find.
Link: https://lore.kernel.org/r/f4d18d470cb90f9cb52ea155b01528ba2e76e8d6.1637243717.git.naveennaidu479@gmail.com
Signed-off-by: Naveen Naidu <naveennaidu479@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci/probe.c')
| -rw-r--r-- | drivers/pci/probe.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 087d3658f75c..c48fe1ab1961 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -206,14 +206,14 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type, * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit * 1 must be clear. */ - if (sz == 0xffffffff) + if (PCI_POSSIBLE_ERROR(sz)) sz = 0; /* * I don't know how l can have all bits set. Copied from old code. * Maybe it fixes a bug on some ancient platform. */ - if (l == 0xffffffff) + if (PCI_POSSIBLE_ERROR(l)) l = 0; if (type == pci_bar_unknown) { @@ -1683,7 +1683,7 @@ static int pci_cfg_space_size_ext(struct pci_dev *dev) if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL) return PCI_CFG_SPACE_SIZE; - if (status == 0xffffffff || pci_ext_cfg_is_aliased(dev)) + if (PCI_POSSIBLE_ERROR(status) || pci_ext_cfg_is_aliased(dev)) return PCI_CFG_SPACE_SIZE; return PCI_CFG_SPACE_EXP_SIZE; @@ -2371,8 +2371,8 @@ bool pci_bus_generic_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l)) return false; - /* Some broken boards return 0 or ~0 if a slot is empty: */ - if (*l == 0xffffffff || *l == 0x00000000 || + /* Some broken boards return 0 or ~0 (PCI_ERROR_RESPONSE) if a slot is empty: */ + if (PCI_POSSIBLE_ERROR(*l) || *l == 0x00000000 || *l == 0x0000ffff || *l == 0xffff0000) return false; |