[LinuxBIOS] Kernel crash output: Memtest86+ output

Richard Smith smithbone at gmail.com
Thu Apr 27 06:28:58 CEST 2006

>  LinuxBIOS + filo
>  Errors from C0000 to EFEFC
>  Walltime Cached  RsvdMem MemMap    Cache ECC Test
>            224M        0  LinuxBIOS on    off std
>  Obviously, memtest86 isn't skipping the cmos -- I managed to pause it just
> as it hit C000, and looked at the error result -- AA 55 was in there.  It's
> reading the cmos, and failing to test it, as it should.

That range is not CMOS.  CMOS is 128 bytes and you access it via
portIO.  Memtest86 never hits CMOS.  Those are your legacy video bios
and other shadow area ranges.  Depending on how they are enabled by
your setup code they may not be writeable.

Doubtfull its a problem though as Linux won't use those area for RAM.

Richard A. Smith

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