i386/151122: [boot] BTX 1.02 crashes on boot

[Guido Falsi]

The following reply was made to PR i386/151122; it has been noted by GNATS.

From: Guido Falsi <mad at madpilot.net>
To: bug-followup at FreeBSD.org, renato.camarao at gmail.com
Cc:  
Subject: Re: i386/151122: [boot] BTX 1.02 crashes on boot
Date: Fri, 10 Jun 2011 11:57:48 +0200

 I performed some more testing following suggestions from John Baldwin.
 
 Inserting simple loops in btxldr (foo: jmp foo) made the system hang
 anyway, even when adding the loop as first statement in btxldr. It looks
 like something times out, but this is just a conjecture.
 
 I tested booting the kernel directly from boot2, bypassing loader, as
 described in boot(8) and got this erro from BTX:
 
 /
 FreeBSD/x86 boot
 Default: 0:ad(0,a)/boot/loader
 boot: 0:da(0,a)/boot/kernel/kernel-_
 int=00000006  err=00000000  efl=00010002  eip=23ec42c6
 eax=0018e070  ebx=00000000  ecx=00000000  edx=a0500004
 esi=ffff6000  edi=0018e070  ebp=000003fa  esp=00210608
 cs=0008  ds=0010  es=0010    fs=0010  gs=0010  ss=0010
 cs:eip=ff ff ff ff ff ff ff ff-ff ff ff ff ff ff ff ff
        ff ff ff ff ff ff ff ff-ff ff ff ff ff ff ff ff
 es:esp=d9 03 00 00 00 00 00 00-00 00 00 00 00 00 20 00
        40 00 60 00 8d 64 24 00-55 4e 44 49 16 1d 00 00
 BTX halted
 
 
 (-_ should be in the same spot. - is the spinning thing, _ is the
 cursor)
 
 After this I start thinking that real blame should go on boot2, loader
 being just a victim. I'm trying to figure out how boot2 works, but it's
 a whole new world to me.
 
 -- 
 Guido Falsi <mad at madpilot.net>