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Abstract
On PowerPC systems that use VFIO PCI pass-through devices, error injection is performed from the host that uses the errinjct tool, which targets devices that are based on their location code. The injected error is then detected and handled on the guest side.
However, certain PCI devices, particularly those devices that are connected through NVMe backplane configurations, do not display a valid location code or identifiable device name on the host. This situation prevents host-side error injection for such devices. Also, guest-initiated error injection for VFIO pass-through devices is not yet supported, limiting end-to-end Enhanced Error Handling (EEH) validation from within the guest environment.
Content
Linux Releases Affected
SUSE Linux Enterprise Server (SLES 16.0) and all supported PowerPC platforms that use VFIO PCI pass-through devices.
IBM Systems Affected
All IBM PowerPC (pseries) systems that use VFIO PCI pass-through devices, particularly those with devices that are connected through backplane slots that do not have location code mapping on the host.
Symptoms
In current PowerPC virtualization environments, VFIO pass-through devices rely on host-based error injection that uses the errinjct tool. This tool requires a valid location code to identify and target the device for EEH testing.
For PCI devices that are connected through a NVMe backplane, the host does not display a unique location code or recognizable identifier. As a result, these devices cannot be used for host-initiated EEH error injection.
The guest-side error injection mechanisms for VFIO pass-through devices are not implemented. This limitation prevents comprehensive testing and validation of EEH recovery paths that are initiated from within the guest operating system.
Workaround
No direct methods exist to perform error injection on VFIO pass-through devices without a valid location code.
To validate EEH recovery, use devices that expose valid location codes and are recognized by the host for testing and verification.
Fix Outlook
The fix for this issue will be included in a later release.
I/O devices impacted
EEH testing and validation are affected for all PCI devices that use VFIO for user-space pass-through. These devices include:
- GPUs
- Network interface cards (NICs)
- Storage controllers (such as NVMe drives)
- Any other hardware bound to vfio-pci for direct guest or user-space assignment
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Document Information
Modified date:
10 November 2025
UID
ibm17247833