[ANNOUNCE] Second paper on BIOS Interrupts as used by Windows XP.

Adam Sulmicki adam at cfar.umd.edu
Thu Nov 7 21:25:01 CET 2002

> 	We have fairly advanced prototype system running house and we
> 	exepect release fairly soon.

seems like we are just down to one (stowstopper) bug.

It seems that we must disable MTRR, or else the stuff just don't work
right (ex: it will fail to boot kernel on switch to protected mode). On
the other hand if we do disable MTRRS stuff work pretty briskily with
lilo/grub/linux/openbsd/etc working.

The system is winfast 6300 with sis630 chipset and pentium III and 128mb

does any one has any idea what sort of interaction could cause such

MTRRs are reported by linux bios are:

Setting fixed MTRRs(0-88) type: UC
Setting fixed MTRRs(0-16) type: WB
DONE fixed MTRRs
Setting variable MTRR 0, base:    0MB, range:   64MB, type WB
Setting variable MTRR 1, base:   64MB, range:   32MB, type WB
Setting variable MTRR 2, base:   96MB, range:   16MB, type WB
Setting variable MTRR 3, base:  112MB, range:    8MB, type WB
DONE variable MTRRs
Clear out the extra MTRR's
call intel_enable_fixed_mtrr()
call intel_enable_var_mtrr()
Leave setup_mtrrs

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