[U-Boot] [PATCH] mtd: pxa3xx_nand: Correct allocation and init bug

[Kevin Smith]

On 10/23/2015 04:14 PM, Scott Wood wrote:
> 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?
No, just wasted memory.  Only the invalid dereference and the bad "chip" 
pointer cause crashes.