Re: [PATCH v2 0/5] #11662 - wic should mount /boot

[Ed Bartosh <ed.bartosh@linux.intel.com>]

On Thu, Jun 29, 2017 at 11:39:42AM +0300, Ed Bartosh wrote:
> On Wed, Jun 28, 2017 at 10:32:27AM -0300, Otavio Salvador wrote:
> > On Wed, Jun 28, 2017 at 4:31 AM, Ed Bartosh <ed.bartosh@linux.intel.com> wrote:
> > > On Tue, Jun 27, 2017 at 05:41:45PM -0300, Fabio Berton wrote:
> > >> The last patch I sent is here:
> > >> https://patchwork.openembedded.org/patch/139252/
> > >>
> > >> We're using this patch internally with Pyro branch. I can rework to
> > >> apply on master.
> > >>
> > >> On 06/27/2017 05:35 PM, Otavio Salvador wrote:
> > >> >On Tue, Jun 27, 2017 at 10:28 AM, Ed Bartosh <ed.bartosh@linux.intel.com> wrote:
> > >> >>The patchset also fixes long standing bug: wic updated fstab
> > >> >>inplace in rootfs directory. This causes other tasks working with
> > >> >>rootfs directory to produce incorrect results or crash. This is
> > >> >>fixed by copying rootfs to the temporary directory before updating
> > >> >>fstab.
> > >> >
> > >> >As you is working on this, please also include Fabio's patch on the
> > >> >patchset. It includes a command like option to disable fstab change at
> > >> >all. For delta-based updates this is imperative.
> > >> >
> > >> >Fabio, could you point him the last patch revision?
> > >> >
> > >
> > > Do we really need that?
> > >
> > > JFYI: Mount point in .wks is an optional field. It makes sense to use it only
> > > if partition needs to be mounted on boot. fstab will not be updated
> > > unless it's explicitly requested by specifying mount points in .wks
> > 
> > It should have support to not touch it. For images which we intend to
> > do delta updates, the content cannot be changed besides the original
> > rootfs generation. So yes, we need that.
> 
> I'm not sure I understand this. If you don't want fstab to be changed
> you should not specify mount points in .wks
> There is only one reason to have mount points in .wks: to make wic to
> change /etc/fstab, which you apparently don't want. So, don't specify
> mount points and you'll have what you want.
> 
> Having additional option for this looks redundand to me.

After thinking a bit more about it I'd propose to have global wic option
to avoid rootfs content changes. Not just fstab updates, but any
changes. For now this option (--no-rootfs-update ?) should prevent creating
images if either mount points are specified or --exclude-path is used in .wks
In future if any other rootfs changing functionality is added to wic it must
conflict with this option.

Does this make sense?

--
Regards,
Ed