On Tue, Jun 28, 2016 at 08:52:20AM +0100, David Howells wrote: > Andy Lutomirski <luto@xxxxxxxxxx> wrote: > > > - skcipher_request_set_crypt(req, &sg[1], &sg[0], sizeof(tmpbuf), iv.x); > > + skcipher_request_set_crypt(req, &sg, &sg, sizeof(tmpbuf), iv.x); > > Don't the sg's have to be different? Aren't they both altered by the process > of reading/writing from them? No they don't have to be different. > > struct rxrpc_skb_priv *sp; > > ... > > + swap(tmpbuf.xl, *(__be64 *)sp); > > + > > + sg_init_one(&sg, sp, sizeof(tmpbuf)); > > ???? I assume you're assuming that the rxrpc_skb_priv struct contents can > arbitrarily replaced temporarily... Of course you can, it's per-skb state. > And using an XCHG-equivalent instruction? This won't work on a 32-bit arch > (apart from one that sports CMPXCHG8 or similar). No this is not using an atomic xchg, whatever gave you that idea? -- Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html