i386/52593: Kernel panic when starting apm

[Kevin Oberman]

>Number:         52593
>Category:       i386
>Synopsis:       Kernel panic when starting apm
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    freebsd-i386
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu May 22 14:30:09 PDT 2003
>Closed-Date:
>Last-Modified:
>Originator:     Kevin Oberman
>Release:        FreeBSD 5.1-BETA i386
>Organization:
ESnet
>Environment:
System: FreeBSD puppeteer.es.net 5.1-BETA FreeBSD 5.1-BETA #0: Thu May 22 10:07:13 PDT 2003 oberman at puppeteer.es.net:/usr/obj/usr/src/sys/IBM-T30-D i386

>Description:
System panics during boot when apm is loaded. May be compiled into the
kernel or loaded at boot time.

The system is an IBM ThinkPad T30 with 1.8 GHz P4 with current (as of
Tuesday) BIOS. System runs fine with no issues if APM is not
loaded (other than lack of apm(4) capability).

The system works fine with a kernel built on May 8. I first noticed
the problem in a system built on May 16 (cvsup about 18:00 UTC).

apm0: <APMBIOS> on motherboard

Fatal trap 12: page fault while in kernel mode
fault virtual address	  = 0x1c
fault code		  = supervisor write, page not present
instruction pointer	  = 0x8:0xc0327e18
stack pointer		  = 0x10:0xc050d976
frame pointer		  = 0x10:0xc050dad2
code segment		  = base 0x0, limit 0xfffff, type 0x1b
			  = DPL 0, pres 1, def32 1, gran 1
processor eflags	  = interrupt enabled, resume, IOPL = 0
current process		  = 0 (swapper)
kernel: type 12 trap, code=0
Stopped at      vm_fault+0x268: cmpxchgl          %edx,0x1c(%ecx)
db> tr
vm_fault(c0541000,c0000000,2,0,c0422d60) at vm_fault+0x268
trap_pfault(c050db6a,0,c00004d8,dbfc0000,c00004d8) at trap_pfault+0x1c8
trap(db8c0018,59880010,dbac0060,1c,0) at trap+0x3bd
calltrap() at calltrap+0x5
--- trap 0xc, eip = 0x5812, esp = 0xc050dbaa, ebp = 0xc050ddb0 ---
(null)(dbc40058,0,530e0102,80202,50592a) at 0x5812
db>

This was transcribed by hand, although I have checked for typos
several times, I may have missed one.

Since I have not heard any similar reports (except one from a T40
owner on mobile), I suspect it is platform dependent.

I am not familiar with the debugger, so I may need to add
information.

Finally, I don't get a dump. The system simply reboots! :-(
>How-To-Repeat:
	Boot with apm driver
>Fix:

	No idea at this time


>Release-Note:
>Audit-Trail:
>Unformatted: