I have an SD flashcard that I use with my USB flashcard reader. I just
started using this on my Ubuntu 5.10 system (kernel 2.6.12-10-686), and it
was working beautifully. It would automount when I plugged it in, I could
read and write to the drive, and it would unmount cleanly. I did this
several times.
This morning, when I plugged the card in everything acted normally until I
tried to transfer files to it, at which point it told me that I did not
have permission to write to the folder (on the flashcard). This new
behavior does not make any sense, since AFAIK I have not changed any
relevant settings! The mount point (and all directories on the mounted
volume) shows me as the owner with rwx permissions. Looking in /etc/mtab,
I see the drive is mounted read-only
/dev/sdc1 /media/flashcard vfat
ro,noexec,nosuid,nodev,quiet,shortname=winnt,uid=1000,gid=1000,umask=077,iocharset=utf8
0 0
I tried to re-mount it read-write in the terminal with
sudo umount /media/flashcard/
sudo mount -t vfat -w /dev/sdc1 /media/flashcard
but I get the following error and the drive does not mount
mount: block device /dev/sdc1 is write-protected but explicit `-w' flag
given
When I plug the card into the reader, I get the
following from dmesg:
Feb 20 21:05:18 localhost kernel: [ 3450.877593] sdc: Write Protect is on
Feb 20 21:05:18 localhost kernel: [ 3450.877619] sdc: Mode Sense: 02 00 80
00
Feb 20 21:05:18 localhost kernel: [ 3450.877631] sdc: assuming drive
cache: write through
Feb 20 21:05:18 localhost kernel: [ 3450.892585] SCSI device sdc: 1002496
512-byte hdwr sectors (513 MB)
Feb 20 21:05:18 localhost kernel: [ 3450.918449] sdc: Write Protect is on
Feb 20 21:05:18 localhost kernel: [ 3450.918473] sdc: Mode Sense: 02 00 80
00
Feb 20 21:05:18 localhost kernel: [ 3450.918485] sdc: assuming drive
cache: write through
Feb 20 21:05:18 localhost kernel: [ 3450.918504]
/dev/scsi/host1/bus0/target0/lun2: p1
Feb 20 21:05:19 localhost kernel: [ 3451.785103] FAT: utf8 is not a
recommended IO charset for FAT filesystems, filesystem will be case
sensitive!
I would imagine that the line, "sdc: Write Protect is on" is related to
the problem. Why this would have changed, however, I have no idea. The
card doesn't seem to have an obvious physical write-protect switch, nor
does the drive. Or is it possible this is still just a software issue
(with hotplug or the usb-storage driver or something)?
Following some stuff the web, I tried plugging it in, letting
it mount, and then using the command
sudo mount -o rw,remount /media/flashcard
to remount it read-write. That appeared to work. /etc/mtab showed the
drive now read-write, and in the terminal I used the rm command to delete
one of the files on the flashcard with no errors messages returned.
However, appearances were deceptive. I umounted, unplugged the card, and
then plugged it back in again. When I looked in the directory, the file
had not actually been deleted. Looking in dmesg I found
[ 1172.172644] SCSI error : <0 0 0 2> return code = 0x8000002
[ 1172.172672] sdc: Current: sense key: Hardware Error
[ 1172.172685] Additional sense: Data phase error
[ 1172.172722] end_request: I/O error, dev sdc, sector 106
[ 1172.172743] Buffer I/O error on device sdc1, logical block 43
[ 1172.172760] lost page write due to I/O error on sdc1
[ 1172.180617] SCSI error : <0 0 0 2> return code = 0x8000002
[ 1172.180642] sdc: Current: sense key: Hardware Error
[ 1172.180654] Additional sense: Data phase error
[ 1172.180690] end_request: I/O error, dev sdc, sector 107
[ 1172.180711] Buffer I/O error on device sdc1, logical block 44
[ 1172.180725] lost page write due to I/O error on sdc1
[ 1172.188608] SCSI error : <0 0 0 2> return code = 0x8000002
[ 1172.188632] sdc: Current: sense key: Hardware Error
[ 1172.188644] Additional sense: Data phase error
...[much more]...
[ 1172.254636] end_request: I/O error, dev sdc, sector 356
[ 1172.260562] SCSI error : <0 0 0 2> return code = 0x8000002
[ 1172.260588] sdc: Current: sense key: Hardware Error
[ 1172.260601] Additional sense: Data phase error
[ 1172.260637] end_request: I/O error, dev sdc, sector 554
[ 1172.268573] SCSI error : <0 0 0 2> return code = 0x8000002
[ 1172.268599] sdc: Current: sense key: Hardware Error
[ 1172.268612] Additional sense: Data phase error
[ 1172.268648] end_request: I/O error, dev sdc, sector 175050
So it looked like that remount didn't do quite what I hoped. I still have
no idea what is going on really. I don't know anything about
write-protection features of flash memory, and I'm not even positive
that's the problem.
The card in question here is a SimpleTech 512 MB SD card. I also tried my
128 MB MMC card, and it also appears to mount read-only and show
"write-protected" in dmesg. I've used these cards for a while and never
had this problem to my knowledge. The card reader I'm using is a SanDisk
12-in-1, from /proc/scsi/usb-storage/1
Quote:
Host scsi1: usb-storage
Vendor: SanDisk
Product: ImageMate 12 in 1 Reader/Writer
Serial Number: 0300492815
Protocol: Transparent SCSI
Transport: Bulk
Quirks:
So, how can I fix this so I can write to my flashcard again? What does it
mean about the card being "write-protected" (clearly something other than
file permissions or mount settings)? What baffles me most is that this
behavior spontaneously changed. I'd like to know why, but right now I'd
just settle for fixing the issue.
Any help is greatly appreciated,
Nick
