bin/41131: Something weird with dd(1)

[dlagno%rambler.ru@localhost]

>Number:         41131
>Category:       bin
>Synopsis:       Something weird with dd(1)
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Apr 03 21:20:00 +0000 2009
>Originator:     Denis Lagno
>Release:        5.0_RC3
>Organization:
>Environment:
NetBSD flam.gado 5.0_RC3 NetBSD 5.0_RC3 (FLAM) #0: Sun Mar 29 08:57:26 MSD 2009 
 
dina%flam.gado@localhost:/volatile/worksrc/netbsd-current/obj/sys/arch/i386/compile/FLAM
 i386
>Description:
Trying to zeroize disk volume:

# dd if=/dev/null of=/dev/rcgd8e         
0+0 records in
0+0 records out
0 bytes transferred in 0.001 secs (0 bytes/sec)


# disklabel cgd8                                                                
              
# /dev/rcgd8d:
type: cgd
disk: cgd
label: fictitious
flags:
bytes/sector: 512
sectors/track: 2048
tracks/cylinder: 1
sectors/cylinder: 2048
cylinders: 472057
total sectors: 966773104
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0           # microseconds
track-to-track seek: 0  # microseconds
drivedata: 0 

7 partitions:
#        size    offset     fstype [fsize bsize cpg/sgs]
 d: 966773104         0     unused      0     0        # (Cyl.      0 - 472057*)
 e: 300000000         0     4.2BSD      0     0     0  # (Cyl.      0 - 146484*)
 f: 666773104 300000000     4.2BSD      0     0     0  # (Cyl. 146484*- 472057*)



# ll /dev/rcgd8e                                                                
              
crw-r-----  1 root  operator        93, 68 Apr  4 00:59 /dev/rcgd8e




# ktruss  dd if=/dev/null of=/dev/rcgd8e 2>&1 | tail -n20
  2318      1 dd       open("/dev/null", 0x602, 0x1b6) = 5
  2318      1 dd       __fstat30(0x5, 0xbfbfea94)  = 0
  2318      1 dd       ioctl(0x5, MTIOCGET, 0xbfbfeaf8) Err#25 ENOTTY
  2318      1 dd       __sysctl(0xbfbfe6d4, 0x2, 0xbbbca674, 0xbfbfe6e0, 0, 0) 
= 0
  2318      1 dd       __sysctl(0xbfbfe5e8, 0x2, 0xbbbd14c0, 0xbfbfe5f0, 0, 0) 
= 0
  2318      1 dd       readlink("/dev/rcgd8e", 0xbfbfe6e5, 0x400) Err#2 ENOENT
  2318      1 dd       break(0x8100000)            = 0
  2318      1 dd       mmap(0, 0x100000, 0x3, 0x14001002, 0xffffffff, 0, 0, 0) 
= 0xbb900000
  2318      1 dd       gettimeofday(0x804d340, 0)  = 0
  2318      1 dd       __sigaction_sigtramp(0x1d, 0xbfbfeb18, 0xbfbfeb00, 
0xbbb2fa50, 0x2) = 0
  2318      1 dd       __sigaction_sigtramp(0x2, 0xbfbfeb18, 0xbfbfeb00, 
0xbbb2fa50, 0x2) = 0
  2318      1 dd       read(0x3, 0xbb901400, 0x200) = 0
       ""
  2318      1 dd       close(0x5)                  = 0
  2318      1 dd       gettimeofday(0xbfbfea78, 0) = 0
  2318      1 dd       write(0x2, 0xbfbfea80, 0x1f) = 31
       "0+0 records in\n0+0 records out\n"
  2318      1 dd       write(0x2, 0xbfbfea80, 0x30) = 48
       "0 bytes transferred in 0.001 secs (0 bytes/sec)\n"
  2318      1 dd       exit(0)





# file /dev/rcgd8e                                                              
              
/dev/rcgd8e: character special

# file -s /dev/rcgd8e
/dev/rcgd8e: Unix Fast File system [v1] (little-endian), last mounted on /mnt2, 
last written at Tue Mar 31 12:09:15 2009, clean flag 1, number of blocks 
25000000, number of data blocks 24609909, number of cylinder groups 265, block 
size 16384, fragment size 2048, minimum percentage of free blocks 5, rotational 
delay 0ms, disk rotational speed 60rps, TIME optimization

>How-To-Repeat:

>Fix: