Chris Murphy <lists@xxxxxxxxxxxxxxxxx> writes: > Hi, > > Short version: > # mkfs.any /dev/vda4 > unable to open /dev/vda4: Device or resource busy > > Curiously /dev/vda4 is just a blank partition, not in use by anything > that I'm aware of. And gdisk is allowed to modify the GPT on /dev/vda > without complaint. This is a snippet from strace of the above command > at the failure point: > > openat(AT_FDCWD, "/dev/vda4", O_RDWR|O_EXCL) = -1 EBUSY (Device or > resource busy) [snip] > format, and /proc/mounts shows > > /dev/vda /run/initramfs/live iso9660 > ro,relatime,nojoliet,check=s,map=n,blocksize=2048 0 0 That mount claims the device, and you can't then also open a partition on that device exclusively. > So it sees the whole vda device as iso9660 and ro? But permits gdisk > to modify some select sectors on vda? I admit it's an ambiguous image. > Is it a duck or is it a rabbit? And therefore best to just look at it, > not make modifications to it. Yet /dev/vda is modifiable, where the > partitions aren't. Hmm. The file system is mounted read-only. It may be that the /device/ is not read-only. HTH, Jeff
