[support-gang] is rolling back firmware dangerous? (on XO-1s especially)

[Kevin Gordon]

On Tue, Feb 18, 2014 at 4:25 PM, James Cameron <quozl at laptop.org> wrote:

> On Tue, Feb 18, 2014 at 09:04:52AM -0500, Kevin Gordon wrote:
> > Thanks for this detailed update.  If i may summarize,  if one is
> > using a 12 or 13 O/S on any architecture, I'm assuming the
> > recommended f/w is the most current,  whether on XO-1, 1.5, 1.75 or
> > 4.  If running 11, well, one is on their own :-)
>
> Your summary disagrees with my view, which is more general: when you
> have a choice of firmware, you should always use the latest.
>
> The latest supports any operating system version, and contains bug
> fixes that reduce your cost of ownership.  For volunteers, cost of
> ownership is critical, as it increases the number of children you can
> serve.
>
> > Any concern I had stems from the cases where some non-XO
> > machines/appliances/ gadgets I have advise to not roll back
> > firmware, ever, as changes to the NVRAM configuration can introduce
> > changes that cause the older firmware to be loaded, but then
> > unusable, thereby turning the device into the proverbial brick.  My
> > understanding, from the above discussion, is that this risk is not
> > present with the XO.  I may be getting old, but I seem to remember
> > being expressly told to *NOT* downgrade my XO-1's from C to B f/w,
> > but that was maybe back in the days when my laptop was made out of
> > wood.
>
> I'm happy to get back into discussion after your summary.
>
> In the general case, we also recommend that you do not downgrade,
> firstly because downgrades to version N from version N+1 are not
> tested before version N is released (doh), but also because we knew of
> certain versions that would brick (in the Q2B and Q2C series).
>
> However, since then we have tested more downgrades to the point we
> know they are safe, and the only bricks due to downgrades happened
> before mass production.
>
> If you are using a prototype XO then you've decided to take the risk.
> A prototype may brick on upgrade.  An upgrade may be forced by an
> operating system install.
>
> > Anecdotally, I have successfully upgraded *many* XO-1s to Q2F19, and
> > they are happily running a custom 11.3 build, so there is certainly
> > no need to 'roll-back' in that environment.  In fact, compared to
> > the f/w "as-shipped", I get some nice USB added
> > functionality/reliability with some weird-ass hubs/ sticks using the
> > newest f/w.
>
> Yes, those are examples of the bugs fixed.  Others include reset of
> the clock to a valid date if the clock battery is lost.
>
> You have all regularly pointed out how important the clock battery is.
>
> > I have not yet upgraded any 11.3 XO 1.5 f/w to current yet.  But,
> > our 11.3 XO 1.5 deployments are now on Q3C07, and that seems to be
> > just peachy.  It's on the list to test Q3C16.
>
> This will bring:
>
> - antenna testing utility,
> - booting from USB drives with embedded hubs, or external USB hubs,
> - allow booting if the internal microSD card is missing,
> - primitive laptop cloning capability,
> - detection of incomplete download of .zd file,
> - allow booting from ISO 9660 images, and hybrid images,
> - reset of the clock to a valid date if the clock battery is lost,
> - lid test,
> - serial terminal and remote diagnosis tools,
> - startup sound customisation,
> - compatibility with USB drives with corrupt directories,
> - compatibility with USB drives with empty extended partitions.
>
> Are you hitting any of these?
>

I believe we were experiencing those USB hub flakiness issues on the 1.5 as
well; I will test that increased function very soon.


> > Why do we continue to use 11.3? [... lack of time ...]
>
> No worries.  Hopefully I've given you some tools that will increase
> the time you have.
>
> (It is irritating that Adam, who started this thread, did not explain
> _why_ he wanted to downgrade firmware, leaving us all to speculate.)
>

Well, as much as it would be fun to throw Mr. Holt under the bus on this, I
must do the mea culpa. :-)  I volunteered to lend Tim and him a slew of
XO-1's to do AP testing, but I asked for him to confirm that if I had to
roll back firmware as well as O/S that it was OK to do so. As it turns out,
I then in the interim upgraded all their f/w to current ( using flash
u:\q2f19.rom ) before handing them over, and all was good, thereby
rendering the initial RFI moot, it would appear.  Again, thanks for all the
info, it's really helpful going forward.

Cheers

KG

>
> --
> James Cameron
> http://quozl.linux.org.au/
> _______________________________________________
> Devel mailing list
> Devel at lists.laptop.org
> http://lists.laptop.org/listinfo/devel
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.laptop.org/pipermail/devel/attachments/20140218/ee1d51dd/attachment.html>