[RFC/PATCH] flash_eraseall: extra care if NOR flash is not BIT_WRITEABLE

[Artem Bityutskiy]

On Thu, 2009-03-26 at 16:41 +0100, Sebastian Andrzej Siewior wrote:
> * Jamie Lokier | 2009-03-26 13:44:18 [+0000]:
> 
> >Artem Bityutskiy wrote:
> >> It sounds wrong to me to make flash_eraseall depend on how JFFS2 is
> >> compiled...
> >
> >It sounds wrong to me as well.
> >
> >What if you're running flash_eraseall on one kernel - it might not
> >even have JFFS2 - and then use the flash later with a different kernel
> >with a different setting.
> 
> I'm sorry. That is actually my point. The layout of the cleanmarker
> (which are used only by JFFS2) depends on a specific kernel switch in
> case of NOR flash which is not BIT_WRITEABLE and userland can't know
> that.
> I've sent a patch to remove the -j option because the generated
> cleanmaker *may* be wrong. Artem replied that he would like to see this
> fixed.
> So here is an attempt to fix this: black listed ubi & data flash but I
> dunno how fix the NOR case where does not have BIT_WRITEABLE bit. A
> commandline switch for those who know what they do?
> Why don't rip out -j and let the kernel create clean marker if it
> needs it?

I looked into your patch closer, and there is no such dependency
actually. Now it looks fine for me.

I can apply them if there are not complaints. But how you have
tested them? I would not want to break 'flash_eraseall' once again :-)

-- 
Best regards,
Artem Bityutskiy (Битюцкий Артём)