Boot, installation, upgrade and post-install
・At end of installation, when the system goes to reboot, the CD-ROM is ejected and throws up lots of errors: "end_request: I/O error, dev sr0, sector 437628". Pressing Enter will reboot and resume normally. These errors are harmless and can be ignored. (539027)
・ In dual boot installs, after using Windows applications that use the FlexNet Publisher, as a license manager, such software will overwrite GRUB, effectively breaking the boot process. This has been fixed for applications including Adobe Photoshop (CS4), Dell Datasafe backup, Autocad 2009,Adobe Flash Builder 4,UtraISO. If you have this problem with a new application, see the bug report to add its signature to prevent future problems (441941)
・ The Wubi Windows installer was reported to be unable to open Windows' boot configuration data store in some (but not all) cases. Investigation of the problems are ongoing (613288)
・ You cannot upgrade if wubi is installed to a partition other than Windows. (610898,653134)
・ Lenovo S10-3 systems don't boot. Temporary workaround: add "intel_idle.max_cstate=0" as a kernel paremeter at boot (634702). A fix already exists that will be available only at release time (647071).
・ Macbook's with EFI will not be able to boot the 64bit (amd64) version of Ubuntu 10.10 live cd. The i386 CDs will work. (633983)
・ When the XHCI module is loaded for USB 3.0 operation the system cannot suspend. Manually unloading XHCI will allow suspend to complete normally. To avoid future suspend problems, the workaround is to add SUSPEND_MODULES="xhci-hcd" to /etc/pm/config.d/unload_module then the system can suspend normally. (522998)
・ Hibernation may be unavailable with automatic partitioning. The default partitioning recipe in the installer will in some cases allocate a swap partition that is smaller than the physical memory in the system. This will prevent the use of hibernation (suspend-to-disk) because the system image will not fit in the swap partition. If you intend to use hibernation with your system, you should ensure that the swap partition's size is at least as large as the system's physical RAM. (345126)
・ I/O error after CD is ejected at end of install. In some cases, ejecting the CD at the end of installation will leave errors on the screen such as:
end_request: I/O error, dev sr0, sector 437628
these error messages indicate that the system is still trying to access some files on the CD, and are harmless except that they obscure the message asking the user to press Enter to reboot. You can safely remove the CD from the tray and press Enter at this point to reboot to your new Ubuntu system. (539027)
・ Upstart jobs cannot be run in a chroot. Upstart jobs cannot be started in a chroot because upstart acts as a service supervisor, and processes within the chroot are unable to communicate with the upstart running outside of the chroot (430224). This will cause some packages that have been converted to use upstart jobs instead of init scripts to fail to upgrade within a chroot. Users are advised to configure their chroots with /sbin/initctl pointing to /bin/true, with the following commands run within the chroot:
dpkg-divert --local --rename --add /sbin/initctl
ln -s /bin/true /sbin/initctl
・ The version of upstart included since Ubuntu 9.10 no longer uses the configuration files in the /etc/event.d directory, looking to /etc/init instead. No automatic migration of changes to /etc/event.d is possible. If you have modified any settings in this directory, you will need to reapply them to /etc/init in the new configuration format by hand. (402759)
・ Performance regressions with ext4 under certain workloads. The default file system for installations of Ubuntu 10.10 is ext4, the latest version in the popular series of Linux extended file systems. ext4 includes a number of performance tuning changes relative to previous versions such as ext3, the file system used by default up to Ubuntu 9.04. These generally produce improvements, but some particular workloads are known to be significantly slower when using ext4 than when using ext3. If you have performance-sensitive applications, we recommend that you run benchmarks using multiple file systems in your environment and select the most appropriate.
・ Use of degraded RAID 1 array may cause data loss in exceptional cases. If each member of a RAID 1 array is separately brought up in degraded mode across subsequent runs of the array with no reassembly in between, there is a risk that the disks will be reported as in sync when they are not, resulting in data loss due to inconsistencies between the data that has been written to each member. This is an unlikely occurrence during normal operations, but admins of systems using RAID 1 arrays should take care during maintenance to avoid this situation. (557429)
・ Avahi will always start even if a .local domain is present. The avahi-daemon package, which implements the mDNS "zeroconf" standard, formerly included a check to avoid running when a conflicting .local DNS domain is present, as it was reported that some ISPs advertise such a .local domain on their networks, leaving Ubuntu hosts unable to see names advertised on the local network (327362). In Ubuntu 9.10, avahi-daemon is started regardless. It is possible that this may cause other problems. If your network is configured this way, you can disable mDNS using the following command:
sudo stop avahi-daemon
sudo sed -e '/^start/,+1s/^/#/' /etc/init/avahi-daemon.conf
・ NSS resolution breaks with LDAP over SSL in Ubuntu Server. Upgrading systems configured to use LDAP via SSL as the first service in the NSS stack (in /etc/nsswitch.conf) leads to broken NSS resolution afterwards such that setuid applications like sudo would stop working. To work around this, switch to the libnss-ldapd package instead of libnss-ldap before the upgrade, or use nscd. (423252)
・ Cryptsetup is not by default compatible with the version in 10.04LTS. An encrypted disk set up under 10.04LTS will fail to properly mount under maverick. This is because, as documented in the /usr/share/doc/cryptsetup/NEWS.Debian.gz, defaults have changed. So to mount a disk which was created in 10.04LTS with cryptsetup, in 10.10 you must specify the cipher as such: cryptsetup -c aes-cbc-plain create h /dev/sdb1 (622762)
Graphics and Display
・ Connected DisplayPort monitors may prevent booting when using the nouveau video driver. (655795)
・ External monitor connected via DisplayPort is not recognized when using the nouveau driver. (655800)
・ Image distortion (vsync) on some AMD ATI cards with the proprietary drivers. (303697)
・ The new Xorg 1.9 available in Maverick is not compatible with nVidia based chipsets that use the (nvidia-96) and (nvidia-173) drivers. (626974)
・ The logo will not display during but when using the Nvidia proprietary driver. (653274)
・ The wrong display port is chosen during install of Apple iMacs (Core i5). If you plug a second screen on the mini display port, you can install ubuntu normally using this 2nd screen. (542660)
・ Non-mirrored dual-screen setups may provide incorrect display on secondary monitor. (619663)
Networking & WiFi
・ 802.11n support for the iwlagn driver has been temporarily disabled. Intel is actively working to get this properly fixed up in the firmware. This workaround should be reverted once updated firmware is available. (630748)
・ "Additional drivers" proposes b43, but the installation fails with "Not supported low-power chip". This affects some Dell Mini 9 models and potentially any system with BCM4312 adapters.(655111)
・ Ubuntu 10.10 does not support the XDMCP protocol for remote graphical logins. Users who require XDMCP support will need to install another display manager, such as wdm or xdm, for this functionality (408417).
・ New drivers preventing "sleep" problem for RTL8111/8168B gigabit network adapter (usually onboard) are missing. (573259)
・ Some fingerprint readers normally supported by fprint are not fully supported yet. Installing fprint from the latest PPA may work (640083, 657017, 657031). See the current bug list for libfprint0 to see if your device is affected and possible workarounds.
・ When running on battery, clicking on the battery icon permanently says "Battery life (estimating...)". This affects some HP, Compaq, Dell and System76 systems (629258).
・Resizing windows with the Ambiance theme by grabbing window borders is difficult. This can be mitigated by switching to the Dust or Clear Looks theme (160311).
・Several panel applets may be displayed twice or overlap. (439448).
Common Desktop Applications
・ It is not possible to create Ubuntu 10.04 USB disks from the Startup Disk Creator in Ubuntu 10.10 due to a backwards incompatibility in the syslinux program.
・Adobe Air is not available for 64-bit.（←いつもじゃねｗ ま、ライブラリかませばいけるんだけど
・GDM does not support XDMCP. The version of gdm included in Ubuntu 10.10 does not support the XDMCP protocol for remote graphical logins. Users who require XDMCP support will need to install another display manager, such as wdm or xdm, for this functionality. (408417)
・ When uploading a file to a website, the file browse window doesn't show a preview when an image is selected. This only happens on some websites, when Flash is installed. It appears such websites replace the Nautilus "Browse" dialog with a Flash version (613886).
・ The Gwibber micro-blogging client no longer permits synching of account details across computers. The client was switched to SQLite for back end storage and to make it faster, but means that syncing of account details across computers is no longer supported.
・The Cheese webcam application has video recording related performance regressions. (610600)
・The Nautilus file manager application will sometimes create a non-existent device after the mount and umount of a device. (548546)