Hi Ross and thank you for having taken the time,
I agree about the fact that if the disk might suffer from random bit flips, I couldn't trust it. In fact, like proposed there (https://wiki.yoctoproject.org/wiki/Build_Performance), I optimised the build performance knowing that the file system image would be built faster at the costs implied, which are (among others) that I could not trust the image.

The only thing that gets on a disk that is totally healthy (because we need to keep away from bit flips) is the download folder with all the tarballs. Still, you know that bit flips can occur, granted that it's much less frequent. The problem here is that it's the first time maybe 3 years that a bit flip occured. So it's not really a problem about disk about to fail, but more about random flips caused by say solar wind or something!

I personnally would be satisfied by the point made by Richard Purdie in bug 5571 (comment 2), that is putting the checksum into the .done file. I believe this would indeed avoid errors like the one we got here. Was it implemented? If somebody did this, do you know the commit id, so I can try to cherry pick it.

Best regards,
Olivier
Le 2014-09-22 12:18, Burton, Ross a écrit :
On 22 September 2014 17:16, Burton, Ross <ross.burton@intel.com> wrote:

No, it wouldn't be hard.

https://bugzilla.yoctoproject.org/show_bug.cgi?id=5571

I hit sent a little early then.  5571 is a related issue, but if
you're a disk which is suffering from random bit flips, then do you
want to trust it to building a file system image that likely is
corrupted?  By extension we should checksum every file we generate
just in case they get corrupted too...

Ross