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8.77. grub

Updated grub packages that fix several bugs are now available for Red Hat Enterprise Linux 6.
The grub packages provide GRUB (Grand Unified Boot Loader), a boot loader capable of booting a wide variety of operating systems.

Bug Fixes

On some systems that are not case sensitive, the "bootx64" command incorrectly launched the GRUB shell instead of booting the GRUB installer. With this update, "bootx64" also checks for the existence of the GRUB booting file (BOOTX64), which allows for using "bootx64" to boot GRUB on systems which are not case sensitive.
A regular expression in the grub-install program could not match multipath devices when the "user_friendly_name" option was set to "no". As a consequence, the user was not able to install the GRUB utility on a specified device. To fix this bug, the regular expression has been updated to match the requested device names. As a result, GRUB now installs successfully.
Prior to this update, exiting the GRUB shell menu and rebooting the ISO file on an extensible firmware interface (EFI) system changed the boot device path, which in turn caused an assert error. As a consequence, GRUB sometimes failed to boot. This update prevents the boot device path from being changed, and as a result, exiting the GRUB shell and rebooting the ISO file now proceeds as expected.
Previously, the biodisk function incorrectly returned "0" instead of the correct values of the read and write calls. Due to this bug, the kernel under some circumstances detected disk errors when booting, which caused the boot to fail. This update fixes the behavior of biodisk, and the boot failure no longer occurs.
Previously, booting GRUB with trusted boot (tboot) enabled under some circumstances caused the tboot screen to be blue, making the text output impossible to read. This update adds a number of conditions for graphic initialization to GRUB, which ensure that the tboot screen displays in normal colors.
Previously, the graphics_cls() and graphics_init() calls did not correctly co-operate with GRUB. As a consequence, booting an ISO file with disabled VGA caused the system to encounter an exception and automatically reboot. With this update, the behavior of the mentioned calls has been corrected and the system now successfully boots with disabled VGA.
BZ#1094978, BZ#1074914, BZ#1048681
When the "splashimage" option parameter was commented out or a serial console was enabled in the /boot/EFI/redhat/grub.cfg file, the kernel did not initialize the efifb graphic back end when booting an EFI system. As a consequence, VGA text consoles displayed a blank screen instead of the intended output. With this update, booting an EFI system uses efifb regardless of whether GRUB splash image or a serial console are used, and the content of VGA consoles now displays as expected.
Prior to this update, if a splash image was not used when booting an EFI system, the serial console displayed a redundant grub_read() failure message during the boot process. With this update, the underlying code has been fixed and booting an EFI system without the GRUB splash image no longer generates redundant failure messages.
Users of grub are advised to upgrade to these updated packages, which fix these bugs.