>Number:         28706
>Category:       kern
>Synopsis:       ahc1: Bus Device Reset Message Sent, Inactive SCB in untaggedQ   -----> hang
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Dec 18 22:18:00 +0000 2004
>Originator:     Lars Nordlund
>Release:        NetBSD 2.99.10
>Organization:
>Environment:
NetBSD glengoyne 2.99.10 NetBSD 2.99.10 (GLENGOYNE) #1: Sat Dec 18 21:41:47 CET 2004  builder@glengoyne:/space/builder/obj_i386/sys/arch/i386/compile/GLENGOYNE i386

>Description:
When using cdparanoia to grab audio tracks from a CD using this device:

cd0 at scsibus0 target 1 lun 0: <PIONEER, DVD-ROM DVD-305, 1.05> cdrom removable
cd0: sync (50.00ns offset 16), 8-bit (20.000MB/s) transfers

the system might hang. Most CDs work fine, but some will cause the hang. Running in console mode I caught this (manually typed from console output, beware of spelling errors):


ahc1: Bus Device Reset Message Sent
Inactive SCB in untaggedQ
Inactive SCB in untaggedQ

uvm_fault(0xcd90c620,0,0,2)->0xe
kernel: page fault trap, code=0
Stopped in pid 438.1 (syslogd) at
  netbsd:scsipi_user_done + 0x26:
  movb $0, 0x5b (%ebx)

The system drops to debugger, I type 'bt'. These are the function call stack of the topmost section:

scsipi_user_done
scsipi_complete
scsipi_done
ahc_done
ahc_search_untagged_queue
ahc_search_qinfifo
ahc_abort_scbs
ahc_handle_devreseet
ahc_handle_scsiint
ahc_intr
Xintr_legacy11

When typing 'reboot 0x04' I get the following:

ahc1: Spurious SCSI interrupt

I had to reboot the machine with the finger.



>How-To-Repeat:
Grab audio from an audio CD in a SCSI CD device, and hope this happens. On my machine, it is fully repeatable.

>Fix:
Nothing known.

I have tried turning off tagged queueing, but that did not help.