Red Hat Bugzilla – Bug 55067
Installer kernel won't boot on P60: machine check exception
Last modified: 2007-04-18 12:37:45 EDT
Description of Problem:
AST Bravo 8060P (Pentium 60) w/48MB will not boot the stock kernel
(2.4.7-BOOT) on the Redhat 7.2 boot.img image. Redhat 7.1 installs and works fine.
Insert Redhat 7.2 CD, boot floppy w/boot.img, turn on machine to install Redhat 7.2.
First, the usual kernel messages before init takes hold... then after:
"Pentium detected w/ F00F bug"
which is followed by repeated:
"CPU#0: Machine Check Exception 0x 10CDE0 (type 0x 9)."
Solution!!! At the boot prompt: 'linux nomce' is the trick that
allows the system to boot and install 7.2 correctly.
This could stand to be documented. Is this a bug or a feature?
I vote for the former, as this machine has worked flawlessly for years.
Will test against the updated 2.4.9-RH kernel when the machine is ready.
It's sort of both a bug and a feature. Recent kernels support the Intel Machine
Check Exception mechanism, a way for the CPU to let the OS know that it has
detected a (fatal) problem in itself or the chipset. In order for the cpu to
know if the chipset has a problem, the CPU has a pin which should be wired to
the chipset pin for this; unfortionatly a number of pentium motherboards have
this pin wired to the 5 Volts line ;(
For the next kernel Red Hat will release I'll disable the MCE on pentium class
machines so "nomce" is then no longer needed.
This should be fixed in the new errata kernels we released yesterday. Thanks for