SD card mounts read-only

[Evgeny Kuznetsov]

On Lenovo 3000 N100 laptop running Ubuntu 8.04 with latest updates, an SD card plugged into the built-in card reader (detected as Ricoh R5C822, see below for lspci output) is detected properly and mounted automagically in GNOME (as it should), but is mounted read-only. It is possible to mount it in RW-mode manually, but this should happen automagically by default, shouldn't it?

lspci output:
05:06.1 SD Host controller: Ricoh Co Ltd R5C822 SD/SDIO/MMC/MS/MSPro Host Adapter (rev 19)
05:06.2 System peripheral: Ricoh Co Ltd R5C843 MMC Host Controller (rev 01)
05:06.3 System peripheral: Ricoh Co Ltd R5C592 Memory Stick Bus Host Adapter (rev 0a)
05:06.4 System peripheral: Ricoh Co Ltd xD-Picture Card Controller (rev 05)

[Chris Coulson (chrisccoulson)]

Could you please type the following in a terminal:

tail -f /var/log/syslog

...then plug in your SD card. Then could you post what was output to the terminal here please.

[Evgeny Kuznetsov (nekr0z)]

Here's what happens in response to card plug:
ay 9 23:50:09 evgkuz kernel: [84226.428195] mmc0: new SD card at address 1234
May 9 23:50:09 evgkuz kernel: [84226.428696] mmcblk0: mmc0:1234 SD02G 1992704KiB
May 9 23:50:09 evgkuz kernel: [84226.428761] mmcblk0: p1
May 9 23:50:09 evgkuz NetworkManager: <debug> [1210362609.992075] nm_hal_device_added(): New device added (hal udi is '/org/freedesktop/Hal/devices/pci_1180_822_mmc_host_mmc_card_rca4660').
May 9 23:50:10 evgkuz NetworkManager: <debug> [1210362610.125819] nm_hal_device_added(): New device added (hal udi is '/org/freedesktop/Hal/devices/storage_serial_0x7cb053b2').
May 9 23:50:10 evgkuz NetworkManager: <debug> [1210362610.215702] nm_hal_device_added(): New device added (hal udi is '/org/freedesktop/Hal/devices/volume_uuid_A70E_5545').
May 9 23:50:10 evgkuz hald: mounted /dev/mmcblk0p1 on behalf of uid 1000
May 9 23:50:10 evgkuz kernel: [84226.993590] FAT: Filesystem panic (dev mmcblk0p1)
May 9 23:50:10 evgkuz kernel: [84226.993598] fat_get_cluster: invalid cluster chain (i_pos 0)
May 9 23:50:10 evgkuz kernel: [84226.993601] File system has been set read-only
May 9 23:50:10 evgkuz kernel: [84226.994360] FAT: Filesystem panic (dev mmcblk0p1)
May 9 23:50:10 evgkuz kernel: [84226.994364] fat_get_cluster: invalid cluster chain (i_pos 0)
May 9 23:50:10 evgkuz kernel: [84227.072470] FAT: Filesystem panic (dev mmcblk0p1)
May 9 23:50:10 evgkuz kernel: [84227.072478] fat_get_cluster: invalid cluster chain (i_pos 0)
May 9 23:50:10 evgkuz kernel: [84227.161783] FAT: Filesystem panic (dev mmcblk0p1)
May 9 23:50:10 evgkuz kernel: [84227.161791] fat_get_cluster: invalid cluster chain (i_pos 0)
May 9 23:50:11 evgkuz kernel: [84227.509875] FAT: Filesystem panic (dev mmcblk0p1)
May 9 23:50:11 evgkuz kernel: [84227.509884] fat_get_cluster: invalid cluster chain (i_pos 0)
May 9 23:50:11 evgkuz kernel: [84227.510343] FAT: Filesystem panic (dev mmcblk0p1)
May 9 23:50:11 evgkuz kernel: [84227.510346] fat_get_cluster: invalid cluster chain (i_pos 0)

Filesystem panic looks really confusing: this very card is fully operational on both Symbian phones and Windows machines and communicators, and those other systems never complain.

[Chris Coulson (chrisccoulson)]

This card has filesystem errors without a doubt. They might be minor and it might work in other devices, but the kernel has mounted it read-only to prevent the filesystem from being damaged further. Please run 'sudo dosfsck -v -a /dev/mmcblk0p1' after unmounting the device (do not do this whilst it is mounted).

In the meantime, I'm marking this as invalid, as it is not a bug. A search over at http://ubuntuforums.org/ will reveal people that have had similar issues, with the same solution here.

Thank you

[Evgeny Kuznetsov (nekr0z)]

Thanks, Chris, it's entirely my fault, I didn't even bother to check if the filesystem was OK, the fact that the card works seamlessly on other devices just made me forget about it. You're surely right this bug is invalid. I heartedly apologise for draining your time and thank you for your quick and detailed response.

[Chris Coulson (chrisccoulson)]

No need to apologise. I know this is not a bug, but I do appreciate that this type of problem can be confusing and misleading to the user, due to the lack of information provided to the user by the system. It seems to affect quite a few users on a regular basis, and I think that there is definately room to improve the 'user-experience' in this area.

Cheers