Setting up the PCIe support

6.10 LPAR mode z/VM guest KVM guest

Use the pci= kernel parameter to configure PCIe support on IBM Z®.

Read syntax diagramSkip visual syntax diagrampci=offpci=nomiopci=norid
pci=off
by default, PCIe device scanning is enabled. Specify this kernel parameter to disable device scanning.
pci=nomio
if available, PCIe uses enhanced instructions as introduced with z15®. Specify this kernel parameter to use the previous instructions.
pci=norid
as of kernel 5.8, PCI function addresses follow an Alternative Routing-ID Interpretation (ARI) conform format if it is supported by the system environment. Specify this kernel parameter to use the previous format.
Attention: Other PCI kernel parameters do not apply to IBM Z and might have adverse effects on your system.
PCIe devices are automatically configured during the system boot process. In contrast to most IBM Z devices, all PCIe devices that are in a configured state are automatically set online. PCIe devices that are in stand-by state are not automatically enabled.