[PATCH v2] mtd: cmdlinepart: fix the wrong partitions number when truncating occurs

[Shmulik Ladkani]

On Wed, 29 Aug 2012 11:16:05 +0300 Artem Bityutskiy <dedekind1 at gmail.com> wrote:
> On Sun, 2012-08-26 at 09:06 +0300, Shmulik Ladkani wrote:
> > root	100m at 0
> > kernel	100m at 100m
> > rootfs	800m at 200m (truncated)
> > user	0 at 1g (truncated)
> > rest	0 at 1g
> 
> Who would benefit from having those 2 0-sized partitions and how? How
> many users/scripts would be confused by this (these 2 ghost partitions
> would be visible in /proc/mtd and sysfs)? How much RAM would we spend
> for creating sysfs files and directories for these ghost partitions
> (note, one sysfs file costs a couple KiB I thing, because 'sizeof
> (struct inode)').
> 
> While you suggestion is clever, do we really benefit from this?

Artem, please note this is just a side effect of what I've suggested
(that its, continue parsing after first truncated partition), not a real
use case I'd expect and intentionally wish to support.

I am used to specify partitions explicitly using size at offset (specifying
offset for all parts, even if sometimes adjacent), and sometimes in an
unsorted fashion.
I never defined some partition that got truncated, so the whole
discussion is theoretical to _my_ usecase.

The only benefit of continuing to parse, is that if there _are_ later
partitions which are defined _explicitly_ with an offset, whose location
is _before_ the truncated partition, these would still be parsed and
registered.

Not so important, and would rarely happen, but simplistic and naive.

And reagrding 0 sized partitions, we can always skip these.

Regards,
Shmulik