SCSI timeout, aic7xxx plus panic

Ulrich Windl (ulrich.windl@rz.uni-regensburg.de)
Thu, 18 Sep 1997 08:34:12 +0200


Yesterday I tried a very limited debug session for the SCSI timeout
reported twice so far. I made an interesting observation:

During a backup from SCSI disk to SCSI tape I hit ^Z to stop the tar.
After about 10 seconds I pressed "fg" and there the panic came along.
Interestingly the ^Z was not delayed, but worked immediately. From other
UNIXes I know that hitting ^Z during tape access can take some time.
Is there a problem with signal processing, especially with resume after a
suspend? Maybe someone not having a AIC7xxx could try this too. I'm not to
much convinced that active termination instead of passive termination on my
CD-ROM drive will solve the problem:

Ulrich

----------

I could reproduce the panic: Pressing ^Z during backup, then waiting
for a few seconds and then pressing "fg". The light on the AHA2940
stayed on continuously then after some seconds the panic came. This
time I haven't copied the console screen, but the values were very
much the same (numscbs = 9, etc.). Previously I had enabled
DEBUG_TIMEOUT in scsi.c, and I have some messages captured on my IDE
drive:

Sep 17 20:54:45 elf syslogd 1.3-0: restart.
Sep 17 20:54:57 elf kernel: klogd 1.3-0, log source = /proc/kmsg started.
Sep 17 20:54:57 elf kernel: Loaded 3307 symbols from /usr/src/linux/System.map.
Sep 17 20:54:57 elf kernel: Symbols match kernel version.
Sep 17 21:00:07 elf kernel: Dump of scsi parameters:
Sep 17 21:00:07 elf kernel: (0) 0:0:2:0 (09:00 0 0 0 0) (0 0 0) (90000 88000 0) a 0 0
Sep 17 21:00:07 elf kernel: (1) 0:0:2:0 (00:00 0 0 0 0) (0 0 0) (0 0 0) 0 0 0
Sep 17 21:00:07 elf kernel: (2) 0:0:1:0 (00:00 0 0 0 0) (0 0 0) (0 0 0) 0 0 0
Sep 17 21:00:07 elf kernel: (3) 0:0:1:0 (00:00 0 0 0 0) (0 0 0) (0 0 0) 0 0 0
Sep 17 21:00:07 elf kernel: (4) 0:0:0:0 (08:06 635324 68 4 9) (0 5 0) (2000 0 0) 8 0 0
Sep 17 21:00:07 elf kernel: (5) 0:0:0:0 (08:06 627672 0 4 0) (0 5 0) (2000 0 0) 8 0 0
Sep 17 21:00:07 elf kernel: (6) 0:0:0:0 (08:06 626148 0 4 0) (0 5 0) (2000 0 0) 8 0 0
Sep 17 21:00:07 elf kernel: (7) 0:0:0:0 (08:06 627696 0 4 0) (0 5 0) (2000 0 0) 8 0 0
Sep 17 21:00:07 elf kernel: (8) 0:0:0:0 (08:06 648944 0 4 0) (0 5 0) (2000 0 0) 8 0 0
Sep 17 21:00:07 elf kernel: (9) 0:0:0:0 (08:06 648804 0 4 0) (0 5 0) (2000 0 0) 8 0 0
Sep 17 21:00:07 elf kernel: (10) 0:0:0:0 (08:06 648820 0 4 0) (0 5 0) (2000 0 0) 8 0 0
Sep 17 21:00:07 elf kernel: (11) 0:0:0:0 (08:06 648840 0 4 0) (0 5 0) (2000 0 0) 8 0 0
Sep 17 21:00:07 elf kernel: wait_for_request = 00000000
Sep 17 21:00:07 elf kernel: Dump of pending block device requests
Sep 17 21:00:07 elf kernel: scsi : aborting command due to timeout : pid 8421, scsi0, channel 0, id
0, lun 0 Read (6) 14 b9 e8 44 00

(After the panic, of course):

elf:/root # cat /proc/scsi/scsi
Attached devices:
Host: scsi0 Channel: 00 Id: 00 Lun: 00
Vendor: CONNER Model: CFP1080S Rev: 4649
Type: Direct-Access ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 01 Lun: 00
Vendor: TOSHIBA Model: CD-ROM XM-5301TA Rev: 1895
Type: CD-ROM ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 02 Lun: 00
Vendor: HP Model: HP35480A Rev: T603
Type: Sequential-Access ANSI SCSI revision: 02
elf:/root #

Adaptec AIC7xxx driver version: 4.1/3.2
Compile Options:
AIC7XXX_RESET_DELAY : 5
AIC7XXX_TAGGED_QUEUEING: Enabled
AIC7XXX_PAGE_ENABLE : Enabled
AIC7XXX_PROC_STATS : Enabled

Adapter Configuration:
SCSI Adapter: Adaptec AHA-294X SCSI host adapter
(AIC-787x chipset)
Host Bus: Single
Base IO: 0xe000
Base IO Memory: 0xf9800000
IRQ: 11
SCBs: Used 8, HW 16, Page 255
Interrupts: 6719
Serial EEPROM: True
Extended Translation: Enabled
SCSI Bus Reset: Enabled
Ultra SCSI: Disabled
Target Disconnect: Enabled