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

[David Laight]

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?

I doubt it is valid to assume that the IP headers is 8 byte
aligned when NET_IP_ALIGN is 2.

	David

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