Messages in this thread | | | Subject | Re: NS83820 2.6.0-test5 driver seems unstable on IA64 | From | Andreas Schwab <> | Date | Tue, 23 Sep 2003 21:16:33 +0200 |
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"David S. Miller" <davem@redhat.com> writes:
> On Tue, 23 Sep 2003 21:09:47 +0200 > Andreas Schwab <schwab@suse.de> wrote: > >> The compiler is allowed to take advantage that there are no unaligned >> accesses. You need to use compiler extensions (like attribute packed) to >> stop it from doing this. > > That's correct, and if the address is misaligned the cpu "traps" > and the kernel fixes up the load/store access to fix it up.
Or the compiler generates code to take advantage of the fact that the lower address bits are zero.
> That's what we're talking about here.
Of course, the kernel language is not ISO C, and never will be.
Andreas.
-- Andreas Schwab, SuSE Labs, schwab@suse.de SuSE Linux AG, Deutschherrnstr. 15-19, D-90429 Nürnberg Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 "And now for something completely different." - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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