From: "Jason A. Donenfeld" <Jason@xxxxxxxxx> Date: Wed, 14 Dec 2016 13:53:10 +0100 > In all current uses of __packed in the code, I think the impact is > precisely zero, because all structures have members in descending > order of size, with each member being a perfect multiple of the one > below it. The __packed is therefore just there for safety, in case > somebody comes in and screws everything up by sticking a u8 in > between. Just marking the structure __packed, whether necessary or not, makes the compiler assume that the members are not aligned and causes byte-by-byte accesses to be performed for words. Never, _ever_, use __packed unless absolutely necessary, it pessimizes the code on cpus that require proper alignment of types. -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
