bin/60698: dump(8) runs endless loop

[Eugene Grosbein]

>Number:         60698
>Category:       bin
>Synopsis:       dump(8) runs endless loop
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Dec 29 10:10:13 PST 2003
>Closed-Date:
>Last-Modified:
>Originator:     Eugene Grosbein
>Release:        FreeBSD 4.9-STABLE i386
>Organization:
Svyaz Service JSC
>Environment:
System: FreeBSD grosbein.pp.ru 4.9-STABLE FreeBSD 4.9-STABLE #8: Sun Dec 14 20:25:57 KRAT 2003 eu at grosbein.pp.ru:/usr/local/obj/usr/local/src/sys/DADV i386
	CPUTYPE=i686 and no other optimizations

>Description:

	Today I've tried to dump(8) my root filesystem:

# dump -f - -a -0 / >/dev/null
  DUMP: Date of this level 0 dump: Tue Dec 30 00:47:21 2003
  DUMP: Date of last level 0 dump: the epoch
  DUMP: Dumping /dev/ad2s1a (/) to standard output
  DUMP: mapping (Pass I) [regular files]
  DUMP: mapping (Pass II) [directories]
  DUMP: estimated 49039 tape blocks.
  DUMP: dumping (Pass III) [directories]
  DUMP: dumping (Pass IV) [regular files]
load: 0.20  cmd: dump 578 [running] 0.09u 0.15s 0% 348k
  DUMP: 88.93% done, finished in 0:00
load: 0.34  cmd: dump 578 [running] 3.17u 0.78s 15% 380k
  DUMP: 305.21% done, finished in 0:00
load: 0.47  cmd: dump 578 [running] 6.29u 1.32s 28% 380k
  DUMP: 514.69% done, finished in 0:00
^C  DUMP: Interrupt received.
  DUMP: Do you want to abort dump?: ("yes" or "no") yes
  DUMP: The ENTIRE dump is aborted.

	It does not finish if I do not interrupt it.

	The same for read-only and read-write mounted root.
	According to fsck(8), the filesystem is clean.

	Hexdump if dump image written by dump(8) shows that it
	repeatedly writes the same 1024 bytes again and again:

# dd if=dump bs=1024 skip=58000 count=1 | env LC_ALL=C hd
00000000  04 00 00 00 cd c9 f0 3f  00 00 00 00 01 00 00 00  |.......?........|
00000010  90 e2 00 00 d6 21 00 00  6c ea 00 00 ea 22 f7 d4  |.....!..l...."..|
00000020  a4 81 01 00 00 00 00 00  ff ff ff ff ff 07 00 00  |................|
00000030  d7 08 da 3f 00 00 00 00  d7 08 da 3f 00 00 00 00  |...?.......?....|
00000040  d7 08 da 3f 00 00 00 00  00 00 00 00 00 00 00 00  |...?............|
00000050  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000080  18 0c 00 00 00 00 00 00  40 00 00 00 61 55 ee 1c  |........ at ...aU..|
00000090  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
000000a0  00 02 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
000000b0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000002a0  00 00 00 00 6e 6f 6e 65  00 00 00 00 00 00 00 00  |....none........|
000002b0  00 00 00 00 00 00 00 00  2f 00 00 00 00 00 00 00  |......../.......|
000002c0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000002f0  00 00 00 00 00 00 00 00  2f 64 65 76 2f 61 64 32  |......../dev/ad2|
00000300  73 31 61 00 00 00 00 00  00 00 00 00 00 00 00 00  |s1a.............|
00000310  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000370  00 00 00 00 00 00 00 00  02 00 00 00 00 00 00 00  |................|
00000380  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000400

	Some more details about my system:

# disklabel /dev/ad2s1
# /dev/ad2s1:
type: ESDI
disk: ad2s1
label:
flags:
bytes/sector: 512
sectors/track: 63
tracks/cylinder: 255
sectors/cylinder: 16065
cylinders: 2609
sectors/unit: 41929587
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0           # milliseconds
track-to-track seek: 0  # milliseconds
drivedata: 0
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a:   131072        0    4.2BSD        0     0     0   # (Cyl.    0 - 8*)
  b:   655360   131072      swap                        # (Cyl.    8*- 48*)
  c: 41929587        0    unused        0     0         # (Cyl.    0 - 2609*)
  e:   524288   786432    4.2BSD        0     0     0   # (Cyl.   48*- 81*)
  f:   262144  1310720    4.2BSD        0     0     0   # (Cyl.   81*- 97*)
  g: 10485760  1572864    4.2BSD        0     0     0   # (Cyl.   97*- 750*)
  h: 29870963 12058624    4.2BSD        0     0     0   # (Cyl.  750*- 2609*)

# df -k /
Filesystem  1K-blocks  Used Avail Capacity  Mounted on
/dev/ad2s1a     63471 48006 10388    82%    /

# mount|grep ad2s1a
/dev/ad2s1a on / (ufs, local, noatime)
	
>How-To-Repeat:
	Hmm, I'd like to known how to not repeat as I cannot make dump.

>Fix:

	Unknown. Broken dump image may be available to a commiter
	on request, compressed size is 13784Kb.
>Release-Note:
>Audit-Trail:
>Unformatted: