From: "Randy.Dunlap" <rddunlap@osdl.org>
To: <jamie@shareable.org>
Cc: <ak@muc.de>, <torvalds@transmeta.com>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Use correct x86 reboot vector
Date: Sat, 10 May 2003 10:09:31 -0700 (PDT) [thread overview]
Message-ID: <33096.4.64.196.31.1052586571.squirrel@www.osdl.org> (raw)
In-Reply-To: <20030510161529.GB29271@mail.jlokier.co.uk>
> Andi Kleen wrote:
>> Extensive discussion by various experts on the discuss@x86-64.org mailing
>> list concluded that the correct vector to restart an 286+ CPU is
>> f000:fff0, not ffff:0000. Both seem to work on current systems, but the
>> first is correct.
>
> You are right. That's what a 286 does when the RESET signal is asserted.
>
> Which is amazing, because I wrote that ffff:0000 and I was reading from the
> Phoenix BIOS book at the time. It was long ago but I'm
> fairly sure I got that address from the book.
>
> I just did some Googling and found that there examples of DOS code fragments
> using both vectors. Also, the original IBM BIOS (as they say) had a long
> jump at the vector, which is presumably one of the many de facto ABIs which
> real mode programmers grew to depend on.
This seems to be a difference from 8086/8088 to the 286.
My iAPX 286 Hardware Reference Manual says that the RESET signal initializes
CS to 0FF0000H and IP to 0FFF0H, while my iAPX 86,88 User's Manual says
that RESET sets CS to 0FFFFh and IP to 0.
~Randy
next prev parent reply other threads:[~2003-05-10 16:56 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-05-10 2:56 [PATCH] Use correct x86 reboot vector Andi Kleen
2003-05-10 3:35 ` CaT
2003-05-10 3:58 ` H. Peter Anvin
2003-05-10 14:49 ` Alan Cox
2003-05-10 16:17 ` Jamie Lokier
2003-05-10 18:47 ` Jos Hulzink
2003-05-11 18:01 ` Eric W. Biederman
2003-05-11 17:24 ` Alan Cox
2003-05-11 19:04 ` Eric W. Biederman
2003-05-12 5:48 ` [PATCH] always shutdown on the bootstrap processor Eric W. Biederman
2003-05-10 16:15 ` [PATCH] Use correct x86 reboot vector Jamie Lokier
2003-05-10 17:09 ` Randy.Dunlap [this message]
2003-05-10 19:41 ` Jos Hulzink
2003-05-10 18:10 ` Jamie Lokier
2003-05-10 20:55 ` Jos Hulzink
2003-05-11 3:50 ` Linus Torvalds
2003-05-11 9:37 ` Jos Hulzink
2003-05-11 14:01 ` Jamie Lokier
2003-05-11 17:38 ` Davide Libenzi
2003-05-11 17:56 ` Eric W. Biederman
2003-05-11 18:23 ` Davide Libenzi
2003-05-11 19:12 ` Eric W. Biederman
2003-05-12 15:36 ` Maciej W. Rozycki
2003-05-13 6:35 ` H. Peter Anvin
2003-05-11 18:38 ` Linus Torvalds
2003-05-11 19:00 ` Matt Mackall
2003-05-11 19:16 ` Eric W. Biederman
2003-05-12 1:07 ` H. Peter Anvin
2003-05-11 19:10 ` Eric W. Biederman
2003-05-11 18:43 ` Christer Weinigel
2003-05-11 20:22 ` wingel
2003-05-11 20:26 ` Davide Libenzi
2003-05-11 17:54 ` Eric W. Biederman
2003-05-13 12:49 Chuck Ebbert
2003-05-13 18:45 ` H. Peter Anvin
2003-05-13 19:04 ` Richard B. Johnson
2003-05-13 19:27 ` H. Peter Anvin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=33096.4.64.196.31.1052586571.squirrel@www.osdl.org \
--to=rddunlap@osdl.org \
--cc=ak@muc.de \
--cc=jamie@shareable.org \
--cc=linux-kernel@vger.kernel.org \
--cc=torvalds@transmeta.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).