Red Hat Bugzilla – Bug 5556
False SMP Multi Processor Detection bug
Last modified: 2015-01-07 18:38:25 EST
After completing an upgrade from RH6.0 to RH6.1 on a 200Mhz Pentium MMX SINGLE PROCESSOR machine on a dual processor mother board (Tyan TomcatIV), the installer automaticly installed an SMP kernel, which then prevented the machine from booting. (We used the graphical installer from an NFS image on the local lan, options were DHCP & etherlink III) Ike Stewart
Additional information, it appears that the installer re configured lilo so the the default "linux" option linked to the SMP kernel, but also left a "linux-up" (uni-processor?) option that does result in the machine booting the single processor kernel. ------- Additional Comments From 10/10/99 14:48 ------- Same problem on SuperMicro P6DGE motherboard. SMP Kernel installed also does not perform power off with poweroff or halt commands.
APM poweroff is not a safe operation to do under SMP (actually, APM isn't defined at all under SMP). Therefore, it doesn't do so. The installer did correctly and detected the dual processor motherboard; there is no way to know if there is a processor in the slot.
Its up to the BIOS to avoid providing a table for 2 CPUs when there is not a dual CPU setup present. If the BIOS doesn't ask the vendor for an upgrade. Because some of these boards assumed the table is burned into ROM you may however be out of luck.
The installer is looking for an SMP capatible motherboard, and upon finding that, will install the SMP kernel and make it the default. The solution to the problem is to boot the uniprocessor kernel (which is installed as well by default . . . just type "linux-up" at the lilo prompt) and then modify /etc/lilo.conf to remove the entry for the SMP kernel and then rerun lilo to affect the change.