Oracle Sun Fire X4470 Product Notes page 44

Oracle Linux, SUSE Linux Enterprise Server (SLES), Red Hat Enterprise Linux (RHEL), and Oracle VM Known Issues
Bug ID
15636521
15643599
44 Sun Fire X4470 Server Product Notes • September 2018
Description
Workaround:
For best results, update to the latest SLES 11 kernel, which will allow the operating system to
boot with no memory in CPU 0 if you have memory installed elsewhere. Refer to the Novell
Documentation Administration Guide for information on obtaining updates using YaST Online
Updater or use Novell patch finder at
Alternatively, you can repopulate the memory slots to ensure that CPU 0 has working memory.
Oracle Linux 5.x.x, RHEL 5.x.x, and SLES 11 SP1 Allow Only Limited Number of Interrupt
Vectors
Issue:
Certain hardware configurations that include many high bandwidth I/O cards with drivers that use
multiple MSI vectors per instance might cause the kernel to run out of interrupts. This situation
might result in a long pause or system hang at boot time or I/O devices that are unusable due to
driver instances unable to get required interrupts. This situation is especially likely to occur for the
Xen Hypervisor and Dom0 with multiple InfiniBand and 10 GbE network cards using SR-IOV, but is
also possible on the SMP kernel.
Affected Operating Systems:
■ Oracle Linux 5.1.0, 5.5, 5.6, 5.7, 5.8, 5.9
■ Red Hat Enterprise Linux (RHEL) 5.1.0, 5.5, 5.6, 5.7, 5.8, 5.9
■ SUSE Linux Enterprise Server (SLES) 11 SP1
Workaround:
Booting with kernel argument pci=nomsi will allow the system to boot with no long pause in UDEV
and no system hang. The system will, however, be forced to use a single IO-APIC PIN interrupt
per function. If you need MSI instead of IO-APIC interrupts, then you might need to use some
combination of the following methods to alleviate the problem:
■ Blacklist some drivers by adding the module name to the text file /etc/modprobe.d/blacklist.
This prevents the module from loading and using the device.
■ Force certain drivers (such as mlx4_core : infiniband) to load last, and take advantage of the
code in those drivers that asks for optimal MSI number of vectors and, if those vectors are not
available, retries with increasingly smaller number of vectors.
SLES 11 Does Not Handle MSIs Properly When VT-d Is Enabled in BIOS
Issue:
If VT-d is enabled in BIOS on a server running SLES 11, all interrupts go to a single processor
(CPU).
Affected Operating System:
■ SUSE Linux Enterprise Server (SLES) 11
Workaround:
■ Use SLES 11, but in the /boot/grub/menu file, append
http://download.novell.com/patch/finder/
nox2apic
to the first line.