ARM network trouble after recent mbuf changes

[Warner Losh]

On Aug 27, 2013, at 9:40 AM, Andrew Turner wrote:

> On Tue, 27 Aug 2013 07:26:03 -0600
> Warner Losh <imp at bsdimp.com> wrote:
> 
>> 
>> On Aug 27, 2013, at 3:28 AM, Andrew Turner wrote:
>> 
>>> On Tue, 27 Aug 2013 08:53:13 +0200
>>> Andre Oppermann <andre at freebsd.org> wrote:
>>>> Please try the patch below to confirm.  If it fixes your problem
>>>> for now I'm going to commit as an immediate fix while searching
>>>> for a better long term stable solution.
>>>> 
>>> 
>>> I tried this with a CTASSERT to check if struct m_hdr is the correct
>>> length. In this test the size is incorrect. It appears __ILP32__ is
>>> not defined on ARM.
>>> 
>>> I have tested a fix suggested by Hans Petter Selasky where we mark
>>> m_hdr with __aligned(8). With this change I can netboot a
>>> PandaBoard.
>> 
>> Isn't that a bug with our arm compiler then?
> 
> No, on ARM EABI the definition of the size of a struct is to be the
> smallest multiple of its alignment. As we are increasing the alignment
> to 8-byte and the struct without this alignment is not a multiple of
> 8-bytes adding this alignment will pad to struct to use the unused 4
> bytes between this and the next struct.

Wrong bug :)

Is it not a bug that __ILP32__ is undefined?

Warner

> Andrew
>> 
>> Warner
>> 
>> 
>