From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@osdl.org>
Subject: Re: Fw: [Bug 6421] New: kernel 2.6.10-2.6.16 on alpha:
 arch/alpha/kernel/io.c, iowrite16_rep() BUG_ON((unsigned long)src & 0x1)
 triggered
Date: Fri, 21 Apr 2006 16:12:27 -0700
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	<200604211945.37129.netdev@axxeo.de>
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To: Ingo Oeser <netdev@axxeo.de>,
	Ivan Kokshaysky <ink@jurassic.park.msu.ru>,
	Richard Henderson <rth@twiddle.net>
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Ingo Oeser <netdev@axxeo.de> wrote:
>
> Stephen Hemminger wrote:
> > Looks like PIO at unaligned addresses doesn't work on alpha...
> 
> Maybe this should be fixed similiar to ioread32_rep in  arch/alpha/kernel/io.c?
> 

I think so, but Ivan thinks networking is bust:


Ivan Kokshaysky <ink@jurassic.park.msu.ru> wrote:
>
> On Fri, Apr 21, 2006 at 04:28:30AM -0700, Andrew Morton wrote:
> > Why is it "silently corrupted"?  It's just misaligned, isn't it?  Networking
> > does that sometimes.
> 
> Because networking does read/write "short" fields in various packet
> header structures. Results are illustrated in a following example:
> 
> char foo[] __attribute__((aligned(8))) = "0123456701234567";
> 
> int main()
> {
> 	short *bar = (short *)&foo[7];
> 	printf("%04x\n", *bar); /* 3037 */
> 	*bar = 0x4241; /* "AB" */
> 	printf("%s\n", foo);
> 	return 0;
> }
> --------
> 0037
> ^^
> 0123456A01234567
>         ^
> Misalignment by two bytes for ints and longs is often unavoidable in
> networking and we can cope with it, but there is no excuse of 1-byte
> misalignment.