Subject: unusual panics on NetBSD/alpha 3.0_* and 4.0_BETA
To: None <port-alpha@netbsd.org, tech-kern@netbsd.org>
From: Eric Schnoebelen <eric@cirr.com>
List: port-alpha
Date: 10/06/2006 22:32:00
------- =_aaaaaaaaaa0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <18196.1160191899.1@egsner.cirr.com>

Gentlebeings;

	I'm running NetBSD/alpha on an assortment of alpha
hardware, but  mostly DS10L's.  One of them, running 3.0_STABLE
(circa 26 July 2006) is seeing the following panics on a
semi-regular basis: (dmesg in the first attachment)

		[-- eric@localhost attached -- Tue Sep 26 19:09:14 2006]
		db> bt
		cpu_Debugger() at netbsd:cpu_Debugger+0x4
		panic() at netbsd:panic+0x1f8
		trap() at netbsd:trap+0x120
		XentUna() at netbsd:XentUna+0x20
		--- unaligned access fault (from ipl 1) ---
		tcp_sack_option() at netbsd:tcp_sack_option+0x13c
		tcp_dooptions() at netbsd:tcp_dooptions+0x278
		tcp_input() at netbsd:tcp_input+0xa20
		ip_input() at netbsd:ip_input+0xb4c
		ipintr() at netbsd:ipintr+0xa0
		netintr() at netbsd:netintr+0x158
		softintr_dispatch() at netbsd:softintr_dispatch+0x160
		exception_return() at netbsd:exception_return+0x7c
		--- root of call graph ---

		[-- eric@localhost attached -- Mon Aug 21 00:39:48 2006]
		db> bt
		cpu_Debugger() at netbsd:cpu_Debugger+0x4
		panic() at netbsd:panic+0x1f8
		pool_get() at netbsd:pool_get+0x1b8
		pool_cache_get_paddr() at netbsd:pool_cache_get_paddr+0x170
		pmap_lev1map_create() at netbsd:pmap_lev1map_create+0x80
		pmap_create() at netbsd:pmap_create+0xe4
		uvmspace_init() at netbsd:uvmspace_init+0xa8
		uvmspace_alloc() at netbsd:uvmspace_alloc+0x58
		uvmspace_exec() at netbsd:uvmspace_exec+0x54
		sys_execve() at netbsd:sys_execve+0x6e0
		syscall_plain() at netbsd:syscall_plain+0xc4
		XentSys() at netbsd:XentSys+0x5c
		--- syscall (59) ---
		--- user mode ---

		[-- eric@localhost attached -- Thu Aug 10 22:37:52 2006]
		db> bt
		cpu_Debugger() at netbsd:cpu_Debugger+0x4
		panic() at netbsd:panic+0x1f8
		trap() at netbsd:trap+0x120
		XentUna() at netbsd:XentUna+0x20
		--- unaligned access fault (from ipl 1) ---
		tcp_sack_option() at netbsd:tcp_sack_option+0x13c
		tcp_dooptions() at netbsd:tcp_dooptions+0x278
		tcp_input() at netbsd:tcp_input+0xa20
		ip_input() at netbsd:ip_input+0xb4c
		ipintr() at netbsd:ipintr+0xa0
		netintr() at netbsd:netintr+0x158
		softintr_dispatch() at netbsd:softintr_dispatch+0x160
		exception_return() at netbsd:exception_return+0x7c
		--- root of call graph ---

		[-- eric@localhost attached -- Thu Aug 10 14:33:47 2006]
		db> bt
		cpu_Debugger() at netbsd:cpu_Debugger+0x4
		panic() at netbsd:panic+0x1f8
		trap() at netbsd:trap+0x120
		XentUna() at netbsd:XentUna+0x20
		--- unaligned access fault (from ipl 1) ---
		tcp_sack_option() at netbsd:tcp_sack_option+0x13c
		tcp_dooptions() at netbsd:tcp_dooptions+0x278
		tcp_input() at netbsd:tcp_input+0xa20
		ip_input() at netbsd:ip_input+0xb4c
		ipintr() at netbsd:ipintr+0xa0
		netintr() at netbsd:netintr+0x158
		softintr_dispatch() at netbsd:softintr_dispatch+0x160
		exception_return() at netbsd:exception_return+0x7c
		--- root of call graph ---

		[-- eric@localhost attached -- Mon Jul 24 17:52:22 2006]
		db> bt
		cpu_Debugger() at netbsd:cpu_Debugger+0x4
		panic() at netbsd:panic+0x1f8
		trap() at netbsd:trap+0x120
		XentUna() at netbsd:XentUna+0x20
		--- unaligned access fault (from ipl 1) ---
		tcp_sack_option() at netbsd:tcp_sack_option+0x13c
		tcp_dooptions() at netbsd:tcp_dooptions+0x278
		tcp_input() at netbsd:tcp_input+0xa20
		ip_input() at netbsd:ip_input+0xb4c
		ipintr() at netbsd:ipintr+0xa0
		netintr() at netbsd:netintr+0x158
		softintr_dispatch() at netbsd:softintr_dispatch+0x160
		exception_return() at netbsd:exception_return+0x7c
		--- root of call graph ---

	The other system, a PC64, which got NetBSD 4.0_BETA
loaded on it a couple of weeks ago (after a couple years of
running 1.6, uptime of neary 2 years when shutdown) generated
the following panic after an (idle) uptime of a couple of
weeks: (dmesg in second attachment)

		[-- eric@localhost attached -- Mon Oct  2 19:51:02 2006]
		db> bt
		cpu_Debugger() at netbsd:cpu_Debugger+0x4
		panic() at netbsd:panic+0x1e8
		machine_check() at netbsd:machine_check+0x304
		interrupt() at netbsd:interrupt+0x2b8
		XentInt() at netbsd:XentInt+0x1c
		--- interrupt (from ipl 0) ---
		ffs_sync() at netbsd:ffs_sync+0x294
		sync_fsync() at netbsd:sync_fsync+0xf0
		VOP_FSYNC() at netbsd:VOP_FSYNC+0x48
		sched_sync() at netbsd:sched_sync+0x26c
		exception_return() at netbsd:exception_return
		--- root of call graph ---

	My gut feeling is that they're related, but I haven't a
bit of proof about it. 

	Any suggestions on what additional information to gather
the next time this happens?

	Thanks,
		Eric

--
Eric Schnoebelen		eric@cirr.com		http://www.cirr.com
    The most feared words in any (large) organization: 
		``We're from corporate - we're here to help you...''

------- =_aaaaaaaaaa0
Content-Type: text/plain; name="dmesg-3.0_STABLE"; charset="us-ascii"
Content-ID: <18196.1160191899.2@egsner.cirr.com>
Content-Description: dmesg from 3.0_STABLE system, NetBSD/alpha on DS10L

Loaded initial symtab at 0xfffffc0000b9ccc0, strtab at 0xfffffc0000c0ec50, # entries 19369
consinit: not using prom console
Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
    The NetBSD Foundation, Inc.  All rights reserved.
Copyright (c) 1982, 1986, 1989, 1991, 1993
    The Regents of the University of California.  All rights reserved.

NetBSD 3.0_STABLE (Milo: based on ALPHA-$Revision: 1.202.2.3 $) #2: Wed Jul 26 08:30:51 CDT 2006
	root@milo.cirr.com:/usr/src/sys/arch/alpha/compile/MILO
AlphaServer DS10L 617 MHz, s/n AY10605785
8192 byte page size, 1 processor.
total memory = 1024 MB
(2912 KB reserved for PROM, 1021 MB used by NetBSD)
avail memory = 993 MB
mainbus0 (root)
cpu0 at mainbus0: ID 0 (primary), 21264A-9
cpu0: VAX FP support, IEEE FP support, Primary Eligible
cpu0: Architecture extensions: 307<PAT,MVI,CIX,FIX,BWX>
tsc0 at mainbus0: 21272 Core Logic Chipset, Cchip rev 0
tsc0: 2 Dchips, 1 memory bus of 16 bytes
tsc0: arrays present: 1024MB (split), 0MB, 0MB, 0MB, Dchip 0 rev 1
tsp0 at tsc0
pci0 at tsp0 bus 0
pci0: i/o space, memory space enabled, rd/line, rd/mult, wr/inv ok
sio0 at pci0 dev 7 function 0: Acer Labs M1543 PCI-ISA Bridge (rev. 0xc3)
tlp0 at pci0 dev 9 function 0: DECchip 21143 Ethernet, pass 4.1
tlp0: interrupting at dec 6600 irq 29
tlp0: Ethernet address 00:10:64:30:1c:a9
tlp0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
tlp1 at pci0 dev 11 function 0: DECchip 21143 Ethernet, pass 4.1
tlp1: interrupting at dec 6600 irq 30
tlp1: Ethernet address 00:10:64:30:1c:ab
tlp1: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
aceride0 at pci0 dev 13 function 0
aceride0: Acer Labs M5229 UDMA IDE Controller (rev. 0xc1)
aceride0: bus-master DMA support present
aceride0: primary channel wired to compatibility mode
aceride0: primary channel interrupting at isa irq 14
atabus0 at aceride0 channel 0
aceride0: secondary channel wired to compatibility mode
aceride0: secondary channel interrupting at isa irq 15
atabus1 at aceride0 channel 1
isa0 at sio0
lpt0 at isa0 port 0x3bc-0x3bf irq 7
com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
com0: console
com1 at isa0 port 0x2f8-0x2ff irq 3: ns16550a, working fifo
pckbc0 at isa0 port 0x60-0x64
pckbdprobe: reset error 5
pmsprobe: reset error 5
pcppi0 at isa0 port 0x61
midi0 at pcppi0: PC speaker
spkr0 at pcppi0
isabeep0 at pcppi0
fdc0 at isa0 port 0x3f0-0x3f7 irq 6 drq 2
mcclock0 at isa0 port 0x70-0x71: mc146818 or compatible
raidattach: Asked for 8 units
Kernelized RAIDframe activated
IPsec: Initialized Security Association Processing.
wd0 at atabus0 drive 0: <Maxtor 53073H4>
wd0: drive supports 16-sector PIO transfers, LBA addressing
wd0: 28629 MB, 58168 cyl, 16 head, 63 sec, 512 bytes/sect x 58633344 sectors
wd0: 32-bit data port
wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 5 (Ultra/100)
wd0(aceride0:0:0): using PIO mode 4, Ultra-DMA mode 2 (Ultra/33) (using DMA)
wd1 at atabus1 drive 0: <Maxtor 6B250R0>
wd1: drive supports 16-sector PIO transfers, LBA48 addressing
wd1: 233 GB, 486344 cyl, 16 head, 63 sec, 512 bytes/sect x 490234752 sectors
wd1: 32-bit data port
wd1: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
wd1(aceride0:1:0): using PIO mode 4, Ultra-DMA mode 2 (Ultra/33) (using DMA)
Searching for RAID components...
stray isa irq 14
stray isa irq 15
root on wd0a dumps on wd0b
mountroot: trying nfs...
mountroot: trying msdos...
mountroot: trying cd9660...
wd0: transfer error, downgrading to Ultra-DMA mode 1
wd0(aceride0:0:0): using PIO mode 4, Ultra-DMA mode 1 (using DMA)
wd0a: DMA error reading fsbn 64 of 64-67 (wd0 bn 64; cn 0 tn 1 sn 1), retrying
stray isa irq 14
wd0: soft error (corrected)
mountroot: trying lfs...
mountroot: trying ffs...
root file system type: ffs
readclock: 6/9/27/0/17/44=>1159316264 (1159311193)
init: copying out path `/sbin/init' 11
stray isa irq 15
wd1: transfer error, downgrading to Ultra-DMA mode 1
wd1(aceride0:1:0): using PIO mode 4, Ultra-DMA mode 1 (using DMA)
wd1a: DMA error reading fsbn 16 of 16-31 (wd1 bn 16; cn 0 tn 0 sn 16), retrying
stray isa irq 15
stray isa irq 15
wd1: soft error (corrected)
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
aceride0:1:0: lost interrupt
	type: ata tc_bcount: 8192 tc_skip: 0
aceride0:1:0: bus-master DMA error: missing interrupt, status=0x21
wd1: transfer error, downgrading to PIO mode 4
wd1(aceride0:1:0): using PIO mode 4
wd1f: DMA error reading fsbn 16 of 16-31 (wd1 bn 280132624; cn 312648 tn 0 sn 16), retrying
stray isa irq 15
stray isa irq 15
wd1: soft error (corrected)
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
stray isa irq 15
setclock: 6/9/27/0/59/47
stray isa irq 15
stray isa irq 15

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Content-Type: text/plain; name="dmesg-4.0_BETA"; charset="us-ascii"
Content-ID: <18196.1160191899.3@egsner.cirr.com>
Content-Description: dmesg from 4.0_BETA system, NetBSD/alpha on a PC64

interface, rev. 0
lxtphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
isp1 at pci0 dev 7 function 0: QLogic 1020 Fast Wide SCSI HBA
isp1: interrupting at eb64+ irq 1
scsibus1 at isp1: 16 targets, 8 luns per target
sio0 at pci0 dev 8 function 0: Intel 82378ZB System I/O (rev. 0x03)
isp2 at pci0 dev 9 function 0: QLogic 1020 Fast Wide SCSI HBA
isp2: interrupting at eb64+ irq 3
scsibus2 at isp2: 16 targets, 8 luns per target
isa0 at sio0
lpt0 at isa0 port 0x3bc-0x3bf irq 7
com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
com0: console
com1 at isa0 port 0x2f8-0x2ff irq 3: ns16550a, working fifo
pckbc0 at isa0 port 0x60-0x64
attimer0 at isa0 port 0x40-0x43: AT Timer
pcppi0 at isa0 port 0x61
midi0 at pcppi0: PC speaker (CPU-intensive output)
spkr0 at pcppi0
isabeep0 at pcppi0
fdc0 at isa0 port 0x3f0-0x3f7 irq 6 drq 2
mcclock0 at isa0 port 0x70-0x71: mc146818 or compatible
pcppi0: attached to attimer0
Kernelized RAIDframe activated
scsibus0: waiting 2 seconds for devices to settle...
scsibus1: waiting 2 seconds for devices to settle...
scsibus2: waiting 2 seconds for devices to settle...
sd0 at scsibus0 target 0 lun 0: <COMPAQPC, WDE4550W, 1.01> disk fixed
sd0: 4094 MB, 6932 cyl, 6 head, 201 sec, 512 bytes/sect x 8386000 sectors
sd0: sync (100.00ns offset 12), 16-bit (20.000MB/s) transfers, tagged queueing
sd1 at scsibus0 target 1 lun 0: <FUJITSU, MAF3364L SUN36G, 1213> disk fixed
sd1: 34732 MB, 24622 cyl, 27 head, 107 sec, 512 bytes/sect x 71132959 sectors
sd1: sync (100.00ns offset 12), 16-bit (20.000MB/s) transfers, tagged queueing
cd0 at scsibus0 target 4 lun 0: <TOSHIBA, CD-ROM XM-4101TA, 1084> cdrom removable
cd0: async, 8-bit transfers
st0 at scsibus0 target 5 lun 0: <ARCHIVE, Python 28388-XXX, 5.40> tape removable
st0: drive empty
st0: async, 8-bit transfers
st1 at scsibus1 target 1 lun 0: <EXABYTE, EXB-89008E030203, V41j> tape removable
st1: density code 39, 1024-byte blocks, write-enabled
st1: sync (100.00ns offset 8), 16-bit (20.000MB/s) transfers
st2 at scsibus1 target 2 lun 0: <EXABYTE, EXB-8900, V41j> tape removable
st2: drive empty
st2: sync (100.00ns offset 8), 16-bit (20.000MB/s) transfers
st3 at scsibus1 target 3 lun 0: <EXABYTE, EXB-89008E00012F, V41b> tape removable
st3: drive empty
st3: sync (100.00ns offset 8), 16-bit (20.000MB/s) transfers
st4 at scsibus1 target 4 lun 0: <EXABYTE, EXB-89008E030203, V39e> tape removable
st4: drive empty
st4: sync (100.00ns offset 8), 16-bit (20.000MB/s) transfers
scsibus2 target 0 lun 0: <EXABYTE, EXB-480, 5.00> changer removable not configured
root on sd0a dumps on sd0b
root file system type: ffs

unexpected machine check:

    mces    = 0x1
    vector  = 0x670
    param   = 0xfffffc0000006000
    pc      = 0xfffffc0000589174
    ra      = 0xfffffc0000589128
    code    = 0x100000000
    curlwp = 0xfffffc000fcfb800
        pid = 7.1, comm = ioflush

panic: machine check
syncing disks... tlp0: receive ring overrun

unexpected machine check:

    mces    = 0x1
    vector  = 0x670
    param   = 0xfffffc0000006000
    pc      = 0xfffffc0000589174
    ra      = 0xfffffc0000589128
    code    = 0x100000000
    curlwp = 0xfffffc000fcfb800
        pid = 7.1, comm = ioflush

panic: machine check

dumping to dev 8,1 offset 523725
dump 256 255 254 253 252 251 250 249 248 247 246 245 244 243 242 241 240 239 238 237 236 235 234 233 232 231 230 229 228 227 226 225 224 223 222 221 220 219 218 217 216 215 214 213 212 211 210 209 208 207 206 205 204 203 202 201 200 199 198 197 196 195 194 193 192 191 190 189 188 187 186 185 184 183 182 181 180 179 178 177 176 175 174 173 172 171 170 169 168 167 166 165 164 163 162 161 160 159 158 157 156 155 154 153 152 151 150 149 148 147 146 145 144 143 142 141 140 139 138 137 136 135 134 133 132 131 130 129 128 127 126 125 124 123 122 121 120 119 118 117 116 115 114 113 112 111 110 109 108 107 106 105 104 103 102 101 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 isp0: DMA error for command on 0.0.0
isp0: BOTCHED cmd for 0.0.0 cmd 0x2a datalen 8192
i/o error


sd0(isp0:0:0:0): polling command not done
panic: scsipi_execute_xs

dumping to dev 8,1 offset 523725
dump device not ready


rebooting...

Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
    The NetBSD Foundation, Inc.  All rights reserved.
Copyright (c) 1982, 1986, 1989, 1991, 1993
    The Regents of the University of California.  All rights reserved.

NetBSD 4.0_BETA (GENERIC) #1: Tue Sep 12 02:09:16 CDT 2006
	eric@egsner.cirr.com:/work/eric/NetBSD-4/obj/alpha/sys/arch/alpha/compile/GENERIC
Digital AlphaPC 64 274 MHz, s/n 
8192 byte page size, 1 processor.
total memory = 256 MB
(2040 KB reserved for PROM, 254 MB used by NetBSD)
avail memory = 241 MB
mainbus0 (root)
cpu0 at mainbus0: ID 0 (primary), 21064A-2
apecs0 at mainbus0: DECchip 21072 Core Logic chipset
apecs0: DC21071-CA pass 2, 128-bit memory bus
apecs0: DC21071-DA pass 2
pci0 at apecs0 bus 0
pci0: i/o space, memory space enabled, rd/line, rd/mult, wr/inv ok
ppb0 at pci0 dev 5 function 0: Digital Equipment DC21050 PCI-PCI Bridge (rev. 0x02)
pci1 at ppb0 bus 1
pci1: memory space enabled, rd/line, wr/inv ok
isp0 at pci1 dev 0 function 0: QLogic 1020 Fast Wide SCSI HBA
isp0: interrupting at eb64+ irq 2
scsibus0 at isp0: 16 targets, 8 luns per target
tlp0 at pci0 dev 6 function 0: DECchip 21140A Ethernet, pass 2.2
tlp0: interrupting at eb64+ irq 0
tlp0: Ethernet address 00:40:05:a3:d7:84
lxtphy0 at tlp0 phy 0: LXT970 10/100 media interface, rev. 0
lxtphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
isp1 at pci0 dev 7 function 0: QLogic 1020 Fast Wide SCSI HBA
isp1: interrupting at eb64+ irq 1
scsibus1 at isp1: 16 targets, 8 luns per target
sio0 at pci0 dev 8 function 0: Intel 82378ZB System I/O (rev. 0x03)
isp2 at pci0 dev 9 function 0: QLogic 1020 Fast Wide SCSI HBA
isp2: interrupting at eb64+ irq 3
scsibus2 at isp2: 16 targets, 8 luns per target
isa0 at sio0
lpt0 at isa0 port 0x3bc-0x3bf irq 7
com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
com0: console
com1 at isa0 port 0x2f8-0x2ff irq 3: ns16550a, working fifo
pckbc0 at isa0 port 0x60-0x64
attimer0 at isa0 port 0x40-0x43: AT Timer
pcppi0 at isa0 port 0x61
midi0 at pcppi0: PC speaker (CPU-intensive output)
spkr0 at pcppi0
isabeep0 at pcppi0
fdc0 at isa0 port 0x3f0-0x3f7 irq 6 drq 2
mcclock0 at isa0 port 0x70-0x71: mc146818 or compatible
pcppi0: attached to attimer0
Kernelized RAIDframe activated
scsibus0: waiting 2 seconds for devices to settle...
scsibus1: waiting 2 seconds for devices to settle...
scsibus2: waiting 2 seconds for devices to settle...
sd0 at scsibus0 target 0 lun 0: <COMPAQPC, WDE4550W, 1.01> disk fixed
sd0: 4094 MB, 6932 cyl, 6 head, 201 sec, 512 bytes/sect x 8386000 sectors
sd0: sync (100.00ns offset 12), 16-bit (20.000MB/s) transfers, tagged queueing
sd1 at scsibus0 target 1 lun 0: <FUJITSU, MAF3364L SUN36G, 1213> disk fixed
sd1: 34732 MB, 24622 cyl, 27 head, 107 sec, 512 bytes/sect x 71132959 sectors
sd1: sync (100.00ns offset 12), 16-bit (20.000MB/s) transfers, tagged queueing
cd0 at scsibus0 target 4 lun 0: <TOSHIBA, CD-ROM XM-4101TA, 1084> cdrom removable
cd0: async, 8-bit transfers
st0 at scsibus0 target 5 lun 0: <ARCHIVE, Python 28388-XXX, 5.40> tape removable
st0: drive empty
st0: async, 8-bit transfers
st1 at scsibus1 target 1 lun 0: <EXABYTE, EXB-89008E030203, V41j> tape removable
st1: density code 39, 1024-byte blocks, write-enabled
st1: sync (100.00ns offset 8), 16-bit (20.000MB/s) transfers
st2 at scsibus1 target 2 lun 0: <EXABYTE, EXB-8900, V41j> tape removable
st2: drive empty
st2: sync (100.00ns offset 8), 16-bit (20.000MB/s) transfers
st3 at scsibus1 target 3 lun 0: <EXABYTE, EXB-89008E00012F, V41b> tape removable
st3: drive empty
st3: sync (100.00ns offset 8), 16-bit (20.000MB/s) transfers
st4 at scsibus1 target 4 lun 0: <EXABYTE, EXB-89008E030203, V39e> tape removable
st4: drive empty
st4: sync (100.00ns offset 8), 16-bit (20.000MB/s) transfers
scsibus2 target 0 lun 0: <EXABYTE, EXB-480, 5.00> changer removable not configured
root on sd0a dumps on sd0b
root file system type: ffs

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