Re: [PATCH 1/1] of: unittest: overlay: ensure proper alignment of copied FDT

From: Frank Rowand
Date: Thu Apr 08 2021 - 10:48:58 EST


On 4/7/21 5:01 PM, Guenter Roeck wrote:
> On 4/7/21 1:59 PM, Frank Rowand wrote:
>> Hi Guenter,
>>
>> On 4/7/21 3:51 PM, frowand.list@xxxxxxxxx wrote:
>>> From: Frank Rowand <frank.rowand@xxxxxxxx>
>>>
>>> The Devicetree standard specifies an 8 byte alignment of the FDT.
>>> Code in libfdt expects this alignment for an FDT image in memory.
>>> kmemdup() returns 4 byte alignment on openrisc. Replace kmemdup()
>>> with kmalloc(), align pointer, memcpy() to get proper alignment.
>>>
>>> The 4 byte alignment exposed a related bug which triggered a crash
>>> on openrisc with:
>>> commit 79edff12060f ("scripts/dtc: Update to upstream version v1.6.0-51-g183df9e9c2b9")
>>> as reported in:
>>> https://lore.kernel.org/lkml/20210327224116.69309-1-linux@xxxxxxxxxxxx/
>>
>> Can you please test this patch?
>>
>
> Sure, will do, after you fixed the problem pointed out by Rob.
>
> Sorry, I should have mentioned it - that problem was the reason
> why I didn't propose a fix myself.

No problem, I was aware of the issue but then spaced on actually
dealing with it.

- Space Cadet Frank

>
> Guenter
>