[fedora-arm] Broken sha512sum in coreutils / forcing alignment fixup and logging in initscripts

[Andy Green]

On 01/08/11 19:59, Somebody in the thread at some point said:

> (1) I think we're agreed that silence (mode 0, ignore), the current
> default, is probably the worst possible value.
>
> (2) It's going to be really, really hard to [i] identify and [ii]
> convince upstreams to fix all alignment issues. Where alignment traps
> may be data-triggered, it will be nearly impossible to have confidence
> that all corner cases have been tested.
>
> I also think that it's unnecessary to eliminate all alignment issues --
> in many cases, kernel fixups may actually be cheaper to run than the
> defensive code necessary to avoid them, and hardware fixups are even
> cheaper. Furthermore, running on an armv7 or higher processor won't
> trigger the alignment traps at all, so we won't even know that there are
> issues (just as we don't know, nor care, in an x86 context).
>
> Thus my recommendation that we warn and fix up the alignment, rather
> than warn and produce wrong results. (If you really want to force
> someone to deal with these issues, you'd want warn+signal, and I would
> strongly oppose making that the default).

Sounds right.  The user is going to google why his log is filling with 
these warnings if he cares and the problem is bad, and this covers his 
code as well as distro code (with the small window where the alignment 
policy is still 0 from running init through actually setting the 
alignment policy to fix+log if he doesn't know about the kernel parameter).

If he doesn't use Fedora initscripts, then he's at the mercy of the 
kernel default alignment policy of "mangle data silently" but that's not 
a Fedora problem.

-Andy