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Date: Wed, 28 Dec 2016 18:53:34 +0000
From: Karl Beldan <karl.beldan@gmail.com>
To: Richard Weinberger <richard@nod.at>
Cc: Brian Norris <computersforpeace@gmail.com>,
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 "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
 Daniel Walter <dwalter@sigma-star.at>, Stable <stable@vger.kernel.org>
Subject: Re: [PATCH v2 01/46] mtdpart: Propagate _get/put_device()
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On Thu, Dec 15, 2016 at 08:51:06AM +0100, Richard Weinberger wrote:
> On 15.12.2016 08:09, Karl Beldan wrote:
> >>> I think this should also go into -stable.
> >>
> >> Why? Do you have real use cases that are broken by this? I understand
> > 
> > I do, some code adding partitions on a gluebi master.
> 
> What exactly are you doing?
> 
> >> this is a problem, but I'm curious on how this satisfies the stable
> >> rules.
> >>
> >> Also, note that this isn't a regression; it's been broken forever and
> >> apparently no one noticed. IMO that raises the bar a bit (but not
> >> impossibly so) for -stable.
> >>
> > 
> > I just encountered the bug yesterday and yes it is obvious it has been
> > broken forever.
> > I don't have strong opinion about these things so no worries.
> 
> If existing stuff is broken, and you can trigger it. Please let us
> know. Then it should go into -stable.
> 

I thought that's what I already did.

Anyways, it didn't require much imagination to come up with a script
triggering the issue so here you are:

#{{

modprobe nandsim
modprobe gluebi
ubiattach -p /dev/mtd1 -b 1
ubimkvol /dev/ubi0 -S 4 -N vol_0
mtdpart add /dev/mtd2 vol_0_0 0 0x1000
tail -F /dev/mtd2 &
while :; do dd bs=1 count=1 if=/dev/mtd3 >/dev/null 2>&1 || break; done
kill -9 %1 # Oops

#}}

 
Karl