OVERVIEW

After booting, device files like /dev/nst0 for a DDS3 HP C1537A scsi tape drive
attached to a pci Adaptec 2940 SCSI adapter are missing.

STEPS TO REPRODUCE

boot.

ACTUAL RESULTS

/dev/nst0 is not present.

There is an error message in the journal:

Feb 28 16:22:03 kato kernel: scsi host0: Adaptec AIC7XXX EISA/VLB/PCI SCSI HBA
DRIVER, Rev 7.0
                                     <Adaptec 2940 SCSI adapter>
                                     aic7870: Single Channel A, SCSI Id=7,
16/253 SCBs
Feb 28 16:22:03 kato kernel: scsi_alloc_sdev: Allocation failure during SCSI
scanning, some SCSI devices might not be configured
Feb 28 16:22:03 kato kernel: scsi_alloc_sdev: Allocation failure during SCSI
scanning, some SCSI devices might not be configured
Feb 28 16:22:03 kato kernel: scsi_alloc_sdev: Allocation failure during SCSI
scanning, some SCSI devices might not be configured
Feb 28 16:22:03 kato kernel: scsi_alloc_sdev: Allocation failure during SCSI
scanning, some SCSI devices might not be configured
Feb 28 16:22:03 kato kernel: scsi_alloc_sdev: Allocation failure during SCSI
scanning, some SCSI devices might not be configured
Feb 28 16:22:03 kato kernel: scsi_alloc_sdev: Allocation failure during SCSI
scanning, some SCSI devices might not be configured
Feb 28 16:22:03 kato kernel: scsi_alloc_sdev: Allocation failure during SCSI
scanning, some SCSI devices might not be configured
Feb 28 16:22:03 kato kernel: shpchp: Standard Hot Plug PCI Controller Driver
version: 0.4

upon issuing "lsmod", kernel module "aic7xxx" is listed, but module "st" is
missing.

EXPECTED RESULTS

/dev/nst0 should be present, kernel module "st" should be loaded.

BUILD DATE & HARDWARE

opensuse leap 42.3 with all patches / updates on x86-64 hardware (asus z170-a
with intel i5-6600).

ADDITIONAL BUILDS AND PLATFORMS

no such bug in opensuse leap 42.2 on Jan 14, 2018 with all paches / updates on
the same machine.

ADDITIONAL INFORMATION

adding the following 2 lines to /etc/init.d/after.local "fixes" the problem:

modprobe -r aic7xxx
modprobe aic7xxx

this produces the following output in the system journal:

M�r 01 12:35:33 kato kernel: scsi host0: Adaptec AIC7XXX EISA/VLB/PCI SCSI HBA
DRIVER, Rev 7.0
                                      <Adaptec 2940 SCSI adapter>
                                      aic7870: Single Channel A, SCSI Id=7,
16/253 SCBs
M�r 01 12:35:34 kato kernel: scsi 0:0:3:0: Sequential-Access HP       C1537A   
       L708 PQ: 0 ANSI: 2
M�r 01 12:35:34 kato kernel: scsi target0:0:3: Beginning Domain Validation
M�r 01 12:35:34 kato kernel: scsi target0:0:3: FAST-10 SCSI 10.0 MB/s ST (100
ns, offset 15)
M�r 01 12:35:34 kato kernel: scsi target0:0:3: Domain Validation skipping write
tests
M�r 01 12:35:34 kato kernel: scsi target0:0:3: Ending Domain Validation
M�r 01 12:35:34 kato kernel: scsi 0:0:3:0: Attached scsi generic sg3 type 1
M�r 01 12:35:34 kato kernel: st: Version 20160209, fixed bufsize 32768, s/g
segs 256
M�r 01 12:35:34 kato kernel: st 0:0:3:0: Attached scsi tape st0
M�r 01 12:35:34 kato kernel: st 0:0:3:0: st0: try direct i/o: yes (alignment 4
B)
M�r 01 12:35:34 kato kernel: osst :I: Tape driver with OnStream support version
0.99.4
                              osst :I: $Id: osst.c,v 1.73 2005/01/01 21:13:34
wriede Exp $

probably, one could blacklist module aic7xxx in /etc/modprobe.d/99-local.conf
and, thus, omit the command "modprobe -r aic7xxx" above. with the current
setup, however, i can monitor whether the bug persists or not.