Bug ID 639528: Kernel.el7.2: Broadwell Home Agent devices have non-compliant BAR.

Last Modified: Apr 10, 2019

Bug Tracker

Affected Product:  See more info
BIG-IP TMOS(all modules)

Known Affected Versions:
13.0.0

Fixed In:
13.0.0 HF1

Opened: Jan 16, 2017
Severity: 4-Minor

Symptoms

Broadwell-EP CPUs have UNCORE devices known as the "Broadwell Home Agent" devices. For both single-socket and dual-socket platforms, this is pci 0000:ff:12.*. These devices have non-compliant BAR's and when the systems with the Broadwell-EP CPUs boot, dmesg output includes as part of early kernel booting messages similar to the following: [ 2.345303] pci 0000:ff:12.0: BAR 2: failed to assign [mem size 0x00000040] [ 2.345306] pci 0000:ff:12.0: BAR 4: failed to assign [mem size 0x00000040] [ 2.345309] pci 0000:ff:12.0: BAR 1: failed to assign [mem size 0x00000010] [ 2.345312] pci 0000:ff:12.0: BAR 3: failed to assign [mem size 0x00000010] [ 2.345315] pci 0000:ff:12.0: BAR 5: failed to assign [mem size 0x00000010] Not related, but also seen is the following: [ 20.123776] mei_me 0000:00:16.0: initialization failed. This is due to the bios configuration not permitting access to the ME (Management Engine). The kernel module for the ME should not be loaded as a result.

Impact

None. This is cosmetic and should not be cause for alarm. The Broadwell-EP Home Agent devices are not used by BIG-IP software, and appear only as part of the UNCORE devices associated with each physical socket.

Conditions

Affects the following platforms: - BIG-IP i10600/i10800 - BIG-IP i7600/i7800 - BIG-IP i5600/i5800 - BIG-IP i4600/i4800 - BIG-IP i2600/i2800 - HRC-i2800 - HRC-i5800 - HRC-i10800

Workaround

None needed: this is cosmetic.

Fix Information

This release includes RHEL7.3 kernels in the BIG-IP 7.2 kernels. RHEL7.3 kernels adds PCI handling for the Broadwell-EP Home Agent devices, which informs the kernel to not attempt to probe or configure the PCI BARs for such devices. Also, this release disables loading the MEI driver, which prevents the mei_me message posting.

Behavior Change