Oracle Linux OS Reports Multiple CE Messages After Hot-plugging 2 PEMs with Different MPS Values Into Same Slot Sequentially (17035011 and 15752501)

After hot-plugging 2 PEMs with different MPS values into the same slot sequentially, the Oracle Linux 6 operating system reports many CE messages. An MPS value can only be auto-negotiated once. Thus, the value negotiated with the first PEM may be different than the value required by the second PEM.

This mismatch may cause a CE (Corrected Error) pop-up. CEs are acceptable messages and do not harm the running system. The operating system may also receive a UE fatal error and stop the system on Sun Blade X4-2B Server Module.

Workaround

Some Linux operating systems have a hotplug patch available for this case. A user may select either of the below kernel parameters for the workaround.

pci=pcie_bus_safe //Set MPS to the minimum size. The PCIe Specification states 128.

pci=pcie_bus_perf //Set MPS to the largest available size. The real value is dependent on the MPS capability of both devices across a PCIe link.

Below are the supported/unsupported Linux operating systems:

• OEL7.0, UEK3 compatible, supported

• OEL6.5, UEK3 compatible, supported

• OEL6.4, UEK2 compatible, unsupported

• OEL6.3, UEK2, unsupported

• OEL5.10, UEK2 compatible, unsupported

• OEL5.9, UEK2 compatible, unsupported

• RHEL7.0, supported

• RHEL6.5, supported

• RHEL6.4, supported

• RHEL5.10, unsupported

• RHEL5.9, unsupported

• SLES11.3, supported

• SLES11.2, supported