Read only file system bs

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1

I am trying to flash full rom. I have a 32 gb flash drive and when I plug it in for the backup, select it. It spits out this error message:
Cp: cannot create regular file ‘/temp/usb/stock-firmware-SHYVANA-20250127.rom’: Read only file system.
Any ideas?

2

not understanding something doesn’t make it BS

doubly so when it’s the result of not following instructions

Your USB needs to have a single FAT32-formatted partition for the backup to be writable to it. The script is trying to mount the first partition on your USB, and it’s highly likely not FAT32 (probably NTFS, which is mounted read-only)

3

It is in fat32 and there is only one partition

4

Yeah, it’s not that. He followed the instructions just fine. It’s a bug in ChromeOS I think, it’s seeing the USB drive as write protected. https://askubuntu.com/questions/101637/usb-turn-write-protection-off

I fixed it by using a MicroSD card in a USB reader.

5

Yeah sometimes the firmware has bugs with sd cards, some devices have this, not all, some devices even allow boot from sd card (very useful for dual bootung windowsand linux on high speed high endurance SD cards)

6

I can’t remember if this is a new feature or not, but this is what I do now:

  1. mkdir /mnt/sd/
  2. mount /dev/mmcblkXpX /mnt/sd/
  3. sudo bash firmware-util.sh
  4. Then, I pick option 5, which is just backing up stock firmware
  5. When prompted, save the backup to /mnt/sd/
  6. Exit firmware-util.sh
  7. umount /mnt/sd
  8. sync
  9. Remove the SD/USB device
  10. Run bash firmware-util.sh again, and install the full UEFI firmware replacement, and when it asks if you want to make a backup, say no (since you already made one)
7

What I would do:

  • Manually mount the usb thumb drive and see if I can copy a file to it, if I can try the script again (this roughly corresponds to what @manouchehri proposed)
  • Mount the USB drive from another PC and check in e.g. gnome-disks, whether there is a strange write protect flag, remove it, try again
  • Check for other labels/ variations of fat, that are non standard (there are bootable flags and all sorts of strange stuff that I would remove, try again
  • Check whether I can run the above stackoverflow command, try again
  • Reformat the drive from another OS, try again
  • Use another thumb drive/ port, try again
  • On the chromebook in a root shell environment, check if the mkfs.fat utility is installed, reformat the drive in the live system (be careful you are messing with the correct drive), format the drive, mount the drive, try again

IMO this is totally solvable and my best guess is that it has nothing to do with the firmware script itself.

8

@manouchehri BTW the call to sync is only of use BEFORE unmounting.

The unmount command should flush data in transit to the drive anyway. But if it makes you feel more confident sync away. If at all it will help best, before unmounting.