[PATCH] nandwrite: add --nobad to write bad blocks

Artem Bityutskiy dedekind1 at gmail.com
Wed Sep 22 03:12:50 EDT 2010


On Wed, 2010-09-22 at 00:23 -0400, Mike Frysinger wrote:
> On Tue, Sep 14, 2010 at 01:26, Artem Bityutskiy wrote:
> > On Mon, 2010-09-13 at 21:21 -0400, Mike Frysinger wrote:
> >> ... policy is for the end user to determine ... this is putting
> >> artificial limits for no real reason that i can see.
> >
> > But the problem is not artificial limits. The problem is that I do not
> > think your option is usable at all, because, as I explained, bad
> > eraseblock is not necessarily writable, it's contents and the state is
> > unpredictable. It may contain unstable bits, for example. You really
> > need to erase it before writing.
> 
> it is completely artificial.  as you said yourself, it is "not
> necessarily writable".  that means i should be able to tell the
> hardware "do XXX" and let the hardware do it.  instead, i'm stuck with
> userspace utils that say "no, you cant do that".  except the only
> thing telling me i cant do that is the userspace utils.  as clearly
> demonstrated, adding this option lets me do what i want -- write to
> pages and change their contents.
> 
> the fact that i might not get the same data back as what i wrote is
> completely irrelevant.  i can already do this to good pages without
> erasing them first.  by your logic, nandwrite should also be
> artificially aborting with "oh, you need to erase these blocks first".
>  but it isnt
> 
> the fact that normally you want to skip badblocks is also irrelevant.
> that's why it is an option the user specifically needs to enable
> themselves.  i dont care if the default policy is "dont write to bad
> blocks".  the default policy has no bearing here.
> -mike

You are pushing for this quite aggressively, so I guess you really need
this :-) And you sound convincing, but give me some time to think about
this please.

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)




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