First a confession. This is about Android but it is using a Linux kernel so I hope this is not entirely off topic.
I have an application on my phone which allows me to clear the 'cache' partition although I had never used that until recently. After using it to clear the cache partition that particular partition will no longer mount. It doesn't appear in the 'mount' list although there are no sign signs of an error.
The only noticeable difference is that I can't download or update any applications because the download process uses the 'cache' partition and it's not mounted. Other than that the phone works normally.
I can get round that by deleting the '/cache' mount point and creating a soft link to another point in the filing system which is then linked to '/ cache' but it's all reset again every time the phone starts.
I've tried manually mounting the 'cache' partition using 'mount -o rw - t ext3 /dev/block/mmcblk0p2 /cache' but that gives me 'Invalid argument'. It can't be a command line argument because there seems to nothing wrong there. I've tried numerous variations of that command with the same error message.
e2fsck on the partition says it's clean.
I made a nandroid backup many months ago long before this happened and have tried restoring the 'cache' partition only from that but the problem remains. I've deduced from that that it cannot be a problem with the partition itself.
So, can anyone suggest reasons why a partition would refuse to mount?