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From: "Petr Vandrovec" <VANDROVE@vc.cvut.cz>
Organization: CC CTU Prague
To: bugghy <bugghy@SAFe-mail.net>
Date: Thu, 15 Jul 2004 17:38:30 +0200
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Subject: Re: address of int80 idt
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On 15 Jul 04 at 18:27, bugghy wrote:
> 
> The problem is that on some kernels 2.4.22 (and I think on 2.6.7, 2.2.26
> and 2.4.26 too) on vmware sidt returns a bogus address for idtr.base:
> idtr.base=0xffc6a370 (2.4.22) 
> 
> If I try to read from /dev/kmem from this address it doesn't work.

It is feature, not a bug... Well, it is bug, but not easily fixable.
Either check 'Disable acceleration' checkbox in VM configuration, or,
if you want portable solution (if your program has root privileges), call 
iopl(3) before issuing sidt. Or issue sidt in the kernel, not in userspace.
                                                        Best regards,
                                                            Petr Vandrovec