On Thu, Oct 29, 2020 at 04:17:35PM -0700, Daniel Xu wrote: > This patchset adds a new `btrfs rescue create-control-device` subcommand > that acts as a convenient way to invoke: > > # mknod --mode=600 c 10 234 /dev/btrfs-control > > on systems that don't have `mknod` installed or when you're lazy.
Well, I don't think the part 'lazy' applies. The whole thing with the control device is simpler that I originally thought. On a system without loaded btrfs module there's no /dev/btrfs-control. This is correct because the device node is created at load time or when btrfs_interface_init is called. Creating just the device node makes no sense because there's nothing handling it. Once module is loaded it appears and works as expected. The only case where the rescue command makes sense is when the module is loaded, device node creatd and then manually deleted. This is possible but highly unlikely. For that reason the rescue command still has some sense but the reasoning needs to reflect how it's related to the module status. As this is docs update only, I'll fix that myself, no need to resend.
