From 9bc9310c8f641234a81f139414fdb5b20b1df8c4 Mon Sep 17 00:00:00 2001 From: Naveen Naidu Date: Thu, 18 Nov 2021 19:33:13 +0530 Subject: [PATCH] PCI: Use PCI_SET_ERROR_RESPONSE() for disconnected devices A config read from a PCI device that doesn't exist or doesn't respond causes a PCI error. There's no real data to return to satisfy the CPU read, so most hardware fabricates ~0 data. Use PCI_SET_ERROR_RESPONSE() to set the error response when we think the device has already been disconnected. This helps unify PCI error response checking and make error checks consistent and easier to find. Link: https://lore.kernel.org/r/29db0a6874716db80757e4e3cdd03562f13eb0cb.1637243717.git.naveennaidu479@gmail.com Signed-off-by: Naveen Naidu Signed-off-by: Bjorn Helgaas --- drivers/pci/access.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/pci/access.c b/drivers/pci/access.c index eac0765d8bed..e1add90494ec 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -529,7 +529,7 @@ EXPORT_SYMBOL(pcie_capability_clear_and_set_dword); int pci_read_config_byte(const struct pci_dev *dev, int where, u8 *val) { if (pci_dev_is_disconnected(dev)) { - *val = ~0; + PCI_SET_ERROR_RESPONSE(val); return PCIBIOS_DEVICE_NOT_FOUND; } return pci_bus_read_config_byte(dev->bus, dev->devfn, where, val); @@ -539,7 +539,7 @@ EXPORT_SYMBOL(pci_read_config_byte); int pci_read_config_word(const struct pci_dev *dev, int where, u16 *val) { if (pci_dev_is_disconnected(dev)) { - *val = ~0; + PCI_SET_ERROR_RESPONSE(val); return PCIBIOS_DEVICE_NOT_FOUND; } return pci_bus_read_config_word(dev->bus, dev->devfn, where, val); @@ -550,7 +550,7 @@ int pci_read_config_dword(const struct pci_dev *dev, int where, u32 *val) { if (pci_dev_is_disconnected(dev)) { - *val = ~0; + PCI_SET_ERROR_RESPONSE(val); return PCIBIOS_DEVICE_NOT_FOUND; } return pci_bus_read_config_dword(dev->bus, dev->devfn, where, val);