[PATCH v9 2/2] lib: checksum: Use aligned accesses for ip_fast_csum and csum_ipv6_magic tests

Guenter Roeck linux at roeck-us.net
Sat Feb 24 01:49:41 AEDT 2024


On 2/23/24 02:28, David Laight wrote:
> From: Christophe Leroy
>> Sent: 23 February 2024 10:07
> ...
>>> +/* Ethernet headers are 14 bytes and NET_IP_ALIGN is used to align them */
>>> +#define IP_ALIGNMENT (14 + NET_IP_ALIGN)
>>
>> Only if no VLAN.
>>
>> When using VLANs it is 4 bytes more. But why do you mind that at all ?
> 
> Wasn't one architecture faulting on a double-register read?
> Where that had to be aligned (probably 8 bytes) but a normal
> memory read could be misaligned?
> 

That was hppa64, and the problem was with its qemu emulation,
not with this code.

Guenter



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