[fedora-arm] Fedora 20 for Raspberry Pi????

Richard W.M. Jones rjones at redhat.com
Fri Dec 27 08:32:30 UTC 2013


On Thu, Dec 26, 2013 at 07:49:58PM +0000, Gordan Bobic wrote:
> On 12/26/2013 02:20 PM, Derek Atkins wrote:
> >Gordan Bobic <gordan at bobich.net> writes:
> >
> >>(e.g. (but not limited to) a large number of packages make little or
> >>no effort to ensure memory accesses are aligned - including the likes
> >>of e2fsprogs, and transparent alignment fixup in hardware is only
> >>available on armv7 and later).
> >
> >I'm surprised that Ted isn't willing to fix issues in e2fsprogs.
> >
> >If you can point me to the upstream bug reports I can ping him to see
> >what's up?
> 
> Take a look here:
> http://comments.gmane.org/gmane.comp.file-systems.ext4/33324
> 
> As has been mentioned before, there is a whole shedload of packages
> that have similar issues - I have seen literally thousands of
> alignment faults get reported (I have the alignment set to fix+warn
> on my armv5tel builders) in various packages during build and test
> stages. Once upon a time I planned to collate the data and get the
> issue reported to all upstream maintainers, but that is a mammoth
> task just to report, let alone fix, and I have very little faith
> there is enough will among the developers to fix all the affected
> packages and ensure they write code that isn't affected by this
> problem going forward.

I disagree that it is even a problem; except in a very small number of
cases where it causes a measurable slowdown.  Is there a way to find
out if a program is doing an excessive number of alignment fixups?

Basically this is an architectural problem in ARM, and not something
developers should go through hoops to fix except in the tiny number of
cases where it causes an actual, measurable problem.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming blog: http://rwmj.wordpress.com
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