Re: port-i386/40752: x86 bootloader panic()/exit() loop

["Jared D. McNeill" <jmcneill%invisible.ca@localhost>]

The following reply was made to PR port-i386/40752; it has been noted by GNATS.

From: "Jared D. McNeill" <jmcneill%invisible.ca@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: port-i386-maintainer%netbsd.org@localhost, 
gnats-admin%netbsd.org@localhost, 
 netbsd-bugs%netbsd.org@localhost
Subject: Re: port-i386/40752: x86 bootloader panic()/exit() loop
Date: Thu, 26 Feb 2009 08:48:31 -0500

 Matthias Drochner wrote:
 > The following reply was made to PR port-i386/40752; it has been noted by 
 > GNATS.
 > 
 > From: Matthias Drochner <M.Drochner%fz-juelich.de@localhost>
 > To: Andrew Doran <ad%NetBSD.org@localhost>
 > Cc: gnats-bugs%NetBSD.org@localhost, 
 > port-i386-maintainer%NetBSD.org@localhost,
 >      gnats-admin%NetBSD.org@localhost, netbsd-bugs%NetBSD.org@localhost
 > Subject: Re: port-i386/40752: x86 bootloader panic()/exit() loop 
 > Date: Wed, 25 Feb 2009 17:33:47 +0100
 > 
 >  This is a multipart MIME message.
 >  
 >  --==_Exmh_52932271007360
 >  Content-Type: text/plain; charset=us-ascii
 >  
 >  
 >  ad%NetBSD.org@localhost said:
 >  > >         for (;;) __asm volatile("hlt");
 >  > 'int 0x19' isn't enough? 
 >  
 >  int 0x18! It is almost there -- formerly, the biosboot start
 >  code did define an "exit" entry point. This got lost when
 >  it was split into "bootxx" and "boot".
 >  The appended patch should fix things and even make the
 >  code a couple of bytes smaller.
 
 ``Ralf Brown's Interrupt List'' says about int 0x18:
 
 Notes: Very few PCs other than those produced by IBM contain BASIC in 
 ROM, so the action is unpredictable on compatibles; this interrupt often 
 reboots the system, and often has no effect at all.
 
 Is this typically the case today?
 
 Cheers,
 Jared