From mboxrd@z Thu Jan  1 00:00:00 1970
From: Scott Wood <scottwood@freescale.com>
Date: Fri, 23 Oct 2015 16:14:21 -0500
Subject: [U-Boot] [PATCH] mtd: pxa3xx_nand: Correct allocation and init
	bug
In-Reply-To: <562A9F4D.4050609@elecsyscorp.com>
References: <1445622596-18764-1-git-send-email-kevin.smith@elecsyscorp.com>
 <1445624429.701.184.camel@freescale.com> <562A90FD.9050907@elecsyscorp.com>
 <1445632454.701.214.camel@freescale.com> <562A9F4D.4050609@elecsyscorp.com>
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On Fri, 2015-10-23 at 20:57 +0000, Kevin Smith wrote:
> On 10/23/2015 03:34 PM, Scott Wood wrote:
> > Does Linux have this problem?  Assuming no, please fix this by making the
> > driver look more like Linux.  At least then it would be the same ugliness.
> There are 2 problems and one improvement:
> 1) Invalid dereference.  This is U-Boot-only code not taken from Linux.  
> Removed.
> 2) Bad pointer math.  This is different from Linux, and I have fixed it 
> by making it more like Linux.

It still doesn't look very much like Linux.  Linux has:
                mtd = (void *)&info[1] + (sizeof(*mtd) + sizeof(*host)) * cs;
                chip = (struct nand_chip *)(&mtd[1]);

> 3) Unnecessary memory allocation.  I just noticed this while 
> investigating my crashes caused by the other two issues.
> 
> > Can you explain how the change in the calculation of "chip" and the
> > allocation size is relevant to the NULL dereference?  Couldn't that be 
> > fixed
> > by just removing the "info->host[0]->mtd" line?
> It's not, they are two separate bugs that crash when I try to load from 
> NAND.  Perhaps I should submit a patch series for this?

The allocation size issue causes a crash, not just wasted memory?

-Scott