I have an SD card with a particular image on it that I wanted to back up before modifying anything in case I broke something. I inserted the card into my (Windows) PC and attempted to use Win32 Disk Imager, but the disk was offline because it had a signature collision, according to diskpart. Google said the solution was to change the unique ID of the disk in diskpart, which I did without writing down the original ID. It still wouldn't come online until I rebooted the PC (which I probably should have done first). Now my PC thinks the card is fine, but when I put it in the Pi and turn it on, it begins the boot sequence but won't progress any further after recognizing storage.
The last few lines of the boot sequence are:
[ 1.325488] mmc1: new high speed SDIO card at address 0001 [ 1.325968] mmc0: host does not support reading read-only switch, assuming write-enable [ 1.348842] mmc0: new high speed SDHC card at address 5048 [ 1.347130] mmcblk0: mmc0:5048 SD8GB 7.47 GiB [ 1.354989] mmcblk0: p1 p2
After that the cursor just stays blinking. Double space on the last line is not a typo.
Edit: after about 7 minutes another line shows:
[422.231548] random: crng init done
Is there a way to get the disk working again without wiping/reformatting etc? The whole point was trying to back it up because I don't have another copy of the image.