Red Hat ENTERPRISE LINUX 5.5 - S 2010, Руководство пользователя

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Chapter 5. Known Issues
310
• Xen guests will not boot using configurations that bind multiple virtualized CPUs to a single CPU.
(
BZ#570056
40
)
• The Xen hypervisor will not start when booting from an iSCSI disk. To work around this issue,
disable the Xen hypervisor's EDD feature with the "edd=off" kernel parameter. For example:
kernel -/xen.gz edd=off
(
BZ#568336
41
)
• Some BIOS implementations initialize interrupt remapping hardware in a way that Xen does not
expect. Consequently, a system might hang during boot, returning the error message:
(XEN) [VT-D]intremap.c:73: remap_entry_to_ioapic_rte: index (74) is larger than remap
table entry size (55)!
To work around this issue, disable the interrupt remapping feature in the BIOS and reboot the
system. (
BZ#563546
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)
• blktap may not function as expected, resulting in slow disk I/O causing the guest to operate slowly
also. To work around this issue guests should be installed using a physical disk (i.e. a real partition
or a logical volume). (
BZ#545692
43
)
• On certain platforms, the mptsas driver may cause kernel warning messages such as the following
to be displayed:
kernel unaligned access to 0xe0000034f327f0ff, ip=0xa0000002040c4870
kernel unaligned access to 0xe0000034f327cbff, ip=0xa0000002040c4870
kernel unaligned access to 0xe00000300c9581ff, ip=0xa0000002040c4870
These messages do not indicate a serious error. The data alignment issue will be fixed in a future
release.
BZ#570000
44
• When booting paravirtualized guests that support gigabyte page tables (i.e. a Fedora 11 guest) on
Red Hat Enterprise Linux 5.4 Xen, the domain may fail to start if more than 2047MB of memory
is configured for the domain. To work around this issue, pass the "
nogbpages
" parameter on the
guest kernel command-line.
(BZ#502826)
45
• Boot parameters are required to enable SR/IOV Virtual Function devices. SR/IOV Virtual Function
devices can only be accessed if the parameter pci_pt_e820_access=on is added to the boot stanza
in the /boot/grub/grub.conf file. For example:
title Red Hat Enterprise Linux Server (2.6.18-152.el5xen)
root (hd0,1)
kernel -/xen.gz-2.6.18-152.el5 com1=115200,8n1 console=com1 iommu=1
module -/vmlinuz-2.6.18-152.el5xen ro root=LABEL=/ console=ttyS0,115200
pci_pt_e820_access=on
This enables the MMCONF access method for the PCI configuration space, a requirement for VF
device support