From: ovek AT arcticnet DOT no (Ove Kaaven)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: pentium RDMSR instruction
Date: Thu, 21 Nov 1996 17:02:24 GMT
Organization: Vplan Programvare AS
Lines: 14
Message-ID: <5734kn$lnr@troll.powertech.no>
References: <571ku3$gf1 AT news2 DOT noc DOT netcom DOT net>
NNTP-Posting-Host: alwayscold.darkness.arcticnet.no
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

mcarter@ wrote:

>I've got the new DJGPP binaries 2.7 for v2.1 and the assembler now recognizes
>Pentium instructions - great!  RDTSC works fine but RDMSR does not.  It gets 
>encoded as 0x0F,0x32 which is right but I get the following error when it is run:

>>Exiting due to signal SIGILL
>>Invalid Opcode at eip=00001581

I think RDMSR is a privileged instruction, and must be run from ring
0. To use it, either your DPMI host must "simulate" it (not too
likely), or you must use a ring 0 host, e.g. cwsdpr0.