Messages in this thread | | | Date | Thu, 1 Aug 2013 14:24:32 -0700 | Subject | Re: [PATCH V2 3/3] ethernet: Convert mac address uses of 6 to ETH_ALEN | From | Olof Johansson <> |
| |
On Thu, Aug 1, 2013 at 2:10 PM, David Miller <davem@davemloft.net> wrote: > From: Russell King - ARM Linux <linux@arm.linux.org.uk> > Date: Thu, 1 Aug 2013 22:06:18 +0100 > >> On Thu, Aug 01, 2013 at 02:04:47PM -0700, Joe Perches wrote: >>> On Thu, 2013-08-01 at 21:58 +0100, Russell King - ARM Linux wrote: >>> > This seems rather obscure - I mean, it's not obvious to driver authors >>> > that should be the case. Would it not be better to make this a little >>> > more obvious somehow? Maybe __aligned(2) against mac_addr? Or >>> > maybe have a debugging check for it? >>> >>> That'd be for David Miller (cc'd). >>> >>> I believe he's argued in the past that any alignment check >>> for mac addresses was unnecessary. >>> >>> For all I know it really might not matter because pasemi >>> can successfully dereference a ushort against an odd char >>> pointer. >>> >>> I just noticed it and thought it'd be better moved. >> >> As can ARM too for years now - either in hardware or via fixup for >> kernel code. > > But probably not a good idea if it's done in a fast path.
This particular driver is for the PA Semi chips, and I very much doubt that compatible hardware will ever show up anywhere else; they're fairly dependent on the I/O architecture of the chip and Apple has not brought those aspects forward in their ARM chips, as far as I know.
So, you might as well leave the code alone for now. It's not used on fast path, and the system definitely handles unaligned accesses for this -- it has for years already.
-Olof
| |