5.4-stable review patch. If anyone has any objections, please let me know.
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From: weiyufeng weiyufeng@kylinos.cn
[ Upstream commit a18a025c2fb5fbf2d1d0606ea0d7441ac90e9c39 ]
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/b12005c0d57bb9d4c8b486724d078b7bd92f8321.163724371... Signed-off-by: Naveen Naidu naveennaidu479@gmail.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Stable-dep-of: e2226dbc4a49 ("PCI: cpqphp: Fix PCIBIOS_* return value confusion") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pci/hotplug/cpqphp_pci.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/pci/hotplug/cpqphp_pci.c b/drivers/pci/hotplug/cpqphp_pci.c index 1b2b3f3b648bc..a20875da4ec70 100644 --- a/drivers/pci/hotplug/cpqphp_pci.c +++ b/drivers/pci/hotplug/cpqphp_pci.c @@ -138,7 +138,7 @@ static int PCI_RefinedAccessConfig(struct pci_bus *bus, unsigned int devfn, u8 o
if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, &vendID) == -1) return -1; - if (vendID == 0xffffffff) + if (PCI_POSSIBLE_ERROR(vendID)) return -1; return pci_bus_read_config_dword(bus, devfn, offset, value); } @@ -251,7 +251,7 @@ static int PCI_GetBusDevHelper(struct controller *ctrl, u8 *bus_num, u8 *dev_num *dev_num = tdevice; ctrl->pci_bus->number = tbus; pci_bus_read_config_dword(ctrl->pci_bus, *dev_num, PCI_VENDOR_ID, &work); - if (!nobridge || (work == 0xffffffff)) + if (!nobridge || PCI_POSSIBLE_ERROR(work)) return 0;
dbg("bus_num %d devfn %d\n", *bus_num, *dev_num);