Date: Sun, 28 Jun 1998 10:12:19 +0930 From: Matthew Thyer <thyerm@camtech.net.au> To: Terry Lambert <tlambert@primenet.com> Cc: FreeBSD CURRENT <current@FreeBSD.ORG> Subject: Re: 'fatal trap 12' on boot (smp and up) Message-ID: <3595916B.D253EB3B@camtech.net.au> References: <199806270339.UAA19025@usr04.primenet.com>
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Except it doesn't do what it should. A Win95/Win98 restart to MSDOS restarts the computer in DOS mode but doesn't restores all vectors. Why Microsoft would want to do this I dont know. The problem is we are relying on another product to do the right thing and it doesn't. With Win95 you could work around it as pressing F8 on boot up and choosing "command line only" would give you DOS with unmodified vectors. But Microsoft have decided to make live harder with Win98 by modifying the vectors even in that case. The problem is obviously in the VM86 code assuming that these vectors are unmodified. Terry Lambert wrote: > > > Nice try Terry but you obviously haven't tried it yourself > > as it doesn't work if you have "options VM86" in your kernel. > > ??? > > It restarts the computer in MS-DOS mode. It restores all vectors and > traps appropriate for MS-DOS. > > > Also see my latest message re: Windows 98. > > I think that what's failing is the VM86 code itself, not the kernel. > > For a running Windows95/98, the machine's vectors are rerouted through > thunked code into the VMM (Vitrual Machine Manager). > > Using the "MS-DOS mode" checkbox causes the machine to soft-reboot > and reset the vectors into the BIOS (and the C:\IO.SYS for INT 21, > etc., but the VM86 code does not rely on those interfaces). > > It works for me on my Windows 95 machine at home, when I have my > external SCSI DISK with Windows 95 on it switched to ID 0 and my > internal FreeBSD disk is ID 1. > > You might want to look into the Windows 95 boot process, as documented > in "Inside Windows 95". > > Terry Lambert > terry@lambert.org > --- > Any opinions in this posting are my own and not those of my present > or previous employers. -- /=====================================================================\ |Work: Matthew.Thyer@dsto.defence.gov.au | Home: thyerm@camtech.net.au| \=====================================================================/ "If it is true that our Universe has a zero net value for all conserved quantities, then it may simply be a fluctuation of the vacuum of some larger space in which our Universe is imbedded. In answer to the question of why it happened, I offer the modest proposal that our Universe is simply one of those things which happen from time to time." E. P. Tryon from "Nature" Vol.246 Dec.14, 1973 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
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