kern/79255: Fixating CDRW with burncd(8) hangs system (DVDR NEC ND-6450A on Compaq NX9020)

[Mikolaj Rydzewski]

>Number:         79255
>Category:       kern
>Synopsis:       Fixating CDRW with burncd(8) hangs system (DVDR NEC ND-6450A on Compaq NX9020)
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Mar 26 16:20:02 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Mikolaj Rydzewski <miki at ceti.pl>
>Release:        FreeBSD 5.3-RELEASE-p5 i386
>Organization:
>Environment:
System: FreeBSD hp.dom 5.3-RELEASE-p5 FreeBSD 5.3-RELEASE-p5 #0: Fri Mar 25 08:58:34 CET 2005 root at hp.dom:/usr/src/sys/i386/compile/NX9020 i386


	HP-Compaq NX9020 notebook,
	DVD recorder, info from dmesg:
	acd0: DVDR <NEC DVD+/-RW ND-6450A/2.36> at ata1-master PIO4
>Description:
	System hangs while fixating CDRW. I have modified burncd(8) to know
	when it happens exactly. It hangs on ioctl(fd, CDRIOCFIXATE, &multi)
	call. It DOES NOT hang when fixating with cdrecord (with camcontrol 
	interface) however. Kernel message while hanging:

	kernel trap 12 with interrupts disabled
	Fatal trap 12: page fault while in kernel mode
	fault virtual address:		0x10068
	fault code:	supervisor read, page not present
	instruction pointer: 0x8:0xc062e439
	stack pointer:	0x10:0xd41f4c68
	frame pointer:	0x10:0xd41f4c6c
	code segment:	base 0x0, limit 0xfffff, type: 0x1b
			dpl 0, pres 1, def32 1, gran 1
	processor eflags:	resume, IOPL=0
	current process:	6 (thread taskq)
	trap number:		12
	panic:			page fault
>How-To-Repeat:
	burncd -s max blank fixate
>Fix:
	Use cdrecord instead of burncd. But cdrecord has got limitations
	with writing DVDs. And I like burncd more ;-)


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