I checked this alot when I developed the btrfs support.
It’s just parted “complaining” it can’t read the partition table correctly. So it’s not an error as such, but more like a warning. The resulting image has worked fine in my tests.
Now you made me look. You are right. There’s no need for that “p” to be there, will be fixed for next version.
@Strit here are some other errors that I’m getting (rpi4, xfce):
( 6/27) Creating temporary files...
Unsupported ioctl: cmd=0x5000940e
Failed to create directory or subvolume "/var": Function not implemented
Unsupported ioctl: cmd=0x5000940e
Failed to create directory or subvolume "/home": Function not implemented
Unsupported ioctl: cmd=0x5000940e
Failed to create directory or subvolume "/srv": Function not implemented
Unsupported ioctl: cmd=0x5000940e
Failed to create directory or subvolume "/var/lib/portables": Function not implemented
Unsupported ioctl: cmd=0x5000940e
Failed to create directory or subvolume "/var/lib/machines": Function not implemented
Unsupported ioctl: cmd=0x5000940e
Failed to create directory or subvolume "/tmp": Function not implemented
Unsupported ioctl: cmd=0x5000940e
Failed to create directory or subvolume "/var/tmp": Function not implemented
Failed to open file "/sys/devices/system/cpu/microcode/reload": Read-only file system
error: command failed to execute correctly
They are all “expected”. At least I saw them all in my tests.
The first section is a package that assumes that all those subvolumes are created if the filesystem is btrfs. But we only create @ and @home with our setup.
The second is one from the Plymouth integration. It’s “fixed” right after when it runs mkinitcpio again, so does not matter.
The third section is just information that some packages assume some directory permissions, but they differ slightly.
And the last one is a packaging issue. Should be fixed next time we update rpi4-post-install package.