An MMIO 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 RESPONSE_IS_PCI_ERROR() to check the response we get when we read data from hardware. This helps unify PCI error response checking and make error checks consistent and easier to find. Signed-off-by: Naveen Naidu <naveennaidu479@xxxxxxxxx> --- drivers/pci/controller/vmd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c index a5987e52700e..db81bc4cfe8c 100644 --- a/drivers/pci/controller/vmd.c +++ b/drivers/pci/controller/vmd.c @@ -538,7 +538,7 @@ static int vmd_get_phys_offsets(struct vmd_dev *vmd, bool native_hint, int ret; ret = pci_read_config_dword(dev, PCI_REG_VMLOCK, &vmlock); - if (ret || vmlock == ~0) + if (ret || RESPONSE_IS_PCI_ERROR(&vmlock)) return -ENODEV; if (MB2_SHADOW_EN(vmlock)) { -- 2.25.1