[dm-crypt] cryptsetup manpage: misleading/imprecise description of --size for resize
gmazyland at gmail.com
Wed Feb 15 20:30:53 CET 2017
On 02/15/2017 07:14 PM, G.raud wrote:
> Incriminated part of the cryptsetup manpage:
> " If --size (in sectors) is not specified, the size of the
> underlying block device is used. "
> In fact the size of the underlying block device is used _to compute_ the
> _maximum_ size that can be made available, which in case of LUKS is not
> the whole block device space. The manpage can be misleading to someone
> who doesn't know dmcrypt well and wants to resize a LUKS container. At
> least append something like "to compute the maximum available size" or
> change to "the whole available space is used" for example.
> The maximum size in the case of LUKS is, I think, the size of the block
> device minus the offset; this could be additionaly stated in the
I think part of this sentence in man page predates the LUKS extension :)
Yes, in LUKS it is the size of the device without the area reserved for header
(visible in luksDump as payload offset).
I changed the man page to mention that.
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