Read-only file system on micro SD

brainvision · 09-15-2012, 03:19 PM

Hi everybody..

I have a strange and boring issue with my micro SD card that I use with my smartphone.. Today, while I was reading a PDF book the phone freezes it self: the only solution was to reboot it!
But.. WOW; 'till that moment the phone doesn't recognize my micro-SD any more!! It doesn't give warnings or messages.. nothing.. the only problem is that my SD card is inserted but the phone won't read it..
I mount the micro sd into my Slackware laptop and it still have partitions but they are all read-only! Every thing I try to do (copy files, move, delete etc) fails with a read-only warning!
So I try to format all from the scratch.. but it is not possible!! It doesn't let me format my SD for the same reason: read-only file system!!

WOW!! It's absurd!!
What can I do? is there a solution for that?
I tried to use fsck, badblocks, mkfs but nothing helped!

fdisk -l output

Code:

Disk /dev/sdb: 15.9 GB, 15918432256 bytes
255 heads, 63 sectors/track, 1935 cylinders, total 31090688 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00031a4f

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1    29027343    14513671+   c  W95 FAT32 (LBA)
/dev/sdb2        29027344    31027343     1000000   83  Linux
/dev/sdb3        31027344    31090687       31672   82  Linux swap

I have a FAT partition for data, a ext2 one used with Link2sd and a swap one.

This is the result I got when trying to format the second partition..

Code:

# mkfs.ext2 /dev/sdb2
mke2fs 1.41.14 (22-Dec-2010)
/dev/sdb2: Read-only file system while setting up superblock

leosubhadeep · 09-15-2012, 04:51 PM

Quote:

Originally Posted by brainvision

Hi everybody..

I have a strange and boring issue with my micro SD card that I use with my smartphone.. Today, while I was reading a PDF book the phone freezes it self: the only solution was to reboot it!
But.. WOW; 'till that moment the phone doesn't recognize my micro-SD any more!! It doesn't give warnings or messages.. nothing.. the only problem is that my SD card is inserted but the phone won't read it..
I mount the micro sd into my Slackware laptop and it still have partitions but they are all read-only! Every thing I try to do (copy files, move, delete etc) fails with a read-only warning!
So I try to format all from the scratch.. but it is not possible!! It doesn't let me format my SD for the same reason: read-only file system!!

WOW!! It's absurd!!
What can I do? is there a solution for that?
I tried to use fsck, badblocks, mkfs but nothing helped!

fdisk -l output

Code:

Disk /dev/sdb: 15.9 GB, 15918432256 bytes
255 heads, 63 sectors/track, 1935 cylinders, total 31090688 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00031a4f

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1    29027343    14513671+   c  W95 FAT32 (LBA)
/dev/sdb2        29027344    31027343     1000000   83  Linux
/dev/sdb3        31027344    31090687       31672   82  Linux swap

I have a FAT partition for data, a ext2 one used with Link2sd and a swap one.

This is the result I got when trying to format the second partition..

Code:

# mkfs.ext2 /dev/sdb2
mke2fs 1.41.14 (22-Dec-2010)
/dev/sdb2: Read-only file system while setting up superblock

Check your card adapter. Ther might be a small slick latch which makes the card read-only. Move it up/down from its existing position. Itś usually on the left side of the adapter.

brainvision · 09-16-2012, 03:58 AM

Sorry but this is not a solution for my problem..
As I said the phone doesn't read the micro SD any more! The adapter is not used in this case..

The problem is the file system, not the adapter!

414N · 09-16-2012, 04:00 AM

Usually, when a filesystem is re-mounted as read-only it means there's some issue on the device and/or on the filesystem.
Did you try a filesystem check on the card?

brainvision · 09-16-2012, 04:23 AM

yea I tried using fsck but it doesn't help, 'cause it says - again - that the file system is read-only and I should use the -n option.. but with that option, no changes could be done on the file system..

Code:

# fsck.ext4 /dev/sdb2   
e2fsck 1.41.14 (22-Dec-2010)
/sbin/e2fsck: Read-only file system while trying to open /dev/sdb2
Disk write-protected; use the -n option to do a read-only
check of the device.

same identical issue with the vfat partition..
If I use the -n option it seems all is fine, but I don't trust this last result..

Code:

# fsck.ext4 -n /dev/sdb2
e2fsck 1.41.14 (22-Dec-2010)
Warning: skipping journal recovery because doing a read-only filesystem check.
/dev/sdb2: clean, 175/62504 files, 90702/250000 blocks

414N · 09-16-2012, 05:09 AM

I have a 4GB USB thumbdrive which behaves like your microSD card when filling it beyond a certain limit: as soon as that limit is crossed, all writes to the device fail and dmesg shows that an error occurred and that the device was re-mounted as read-only.
I suspect your device is dying on you, but I would first perform some other tests on other machines and OSes before trying something that can't be easily undone.
Of course, a backup of your most important data -- if not all -- on your device is warmly suggested

jefro · 09-16-2012, 02:28 PM

Re-partition it and format it and put the files back on.

I'd suspect the flash is bad myself.