Re: [PATCH v4 02/29] rxrpc: Avoid using stack memory in SG lists in rxkad

From: Herbert Xu
Date: Tue Jun 28 2016 - 05:45:31 EST


On Tue, Jun 28, 2016 at 10:07:44AM +0100, David Howells wrote:
>
> Since it's (more or less) a one off piece of memory, why not kmalloc it
> temporarily rather than expanding the connection struct? Also, the bit where
> you put a second rxrpc_crypt in just so that it happens to give you a 16-byte
> slot by adjacency is pretty icky. It would be much better to use a union
> instead:
>
> union {
> struct rxrpc_crypt csum_iv; /* packet checksum base */
> __be32 tmpbuf[4];
> };

Feel free to send your own patch to do this.

> Note also that the above doesn't guarantee that the struct will be inside of a
> single page. It would need an alignment of 16 for that - but you only have
> one sg. Could that be a problem?

No it's not a problem.
--
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