[OE-core] [PATCH] lib/oe/rootfs: Fix DEBUGFS generation when using opkg

[Patrick Ohly]

On Mon, 2016-05-02 at 11:15 -0500, Alejandro del Castillo wrote:
> 
> On 05/02/2016 08:39 AM, Patrick Ohly wrote:
> > On Fri, 2016-04-22 at 14:51 +0100, Richard Purdie wrote:
> >> When enabling extra DEBUGFS image generation with opkg, errors are seen like:
> >>
> >> ERROR: core-image-minimal-1.0-r0 do_rootfs: Cannot get the installed packages list. Command '/media/build1/poky/build/tmp/sysroots/x86_64-linux/usr/bin/opkg -f /media/build1/poky/build/tmp/work/qemux86_64-poky-linux/core-image-minimal/1.0-r0/opkg.conf -o /media/build1/poky/build/tmp/work/qemux86_64-poky-linux/core-image-minimal/1.0-r0/rootfs  --force_postinstall --prefer-arch-to-version   status' returned 0 and stderr:
> >> Collected errors:
> >>  * file_md5sum_alloc: Failed to open
> >> file /media/build1/poky/build/tmp/work/qemux86_64-poky-linux/core-image-minimal/1.0-r0/rootfs/etc/syslog-startup.conf.busybox: No such file or directory.
> >>  * file_md5sum_alloc: Failed to open
> >> file /media/build1/poky/build/tmp/work/qemux86_64-poky-linux/core-image-minimal/1.0-r0/rootfs/etc/fstab: No such file or directory.
> >>
> >> basically for all CONFFILES in the image. This is due to the file
> >> rearranging
> >> the rootfs generation code does. If we preserve the /etc directory,
> >> the avoids the problem.
> > 
> > It avoids the problem, but it does not address the root cause (IMHO).
> > Should opkg really complain about missing configuration files? It is
> > perhaps an edge case, but besides editing a configuration file
> > *removing* it entirely may also be a valid user modification.
> > 
> > The usage of opkg here is during image building, but the operation
> > itself (opkg status) is not specific to image creation and thus should
> > be able to handle arbitrary states of /etc and the config files in
> > general.
> 
> Opkg status is supposed to give you the state of all your installed packages.
> Currently is pretty rough data: it dumps into stdout the internal metadata that
> tracks package info and promotes to error any inconsistency, like conffiles not
> being present.

But how does opkg know that "config file not present" is an error? It
depends on the the semantic of the file and thus the package providing
the file. It's not declared explicitly, so it is a fairly arbitrary
judgment call to treat "missing" as error.

> Looking at pacakge_manager.py, opkg status is being called on OpkgPkgsList.
> Seems to me that if the purpose is to get all installed packages, then "opkg
> list-installed" is the correct command. Looking at dpkg (DpkgPkgsList),
> "dpkg-query -W" is being called, which I think maps to opkg list-installed, not
> to opkg status.

That indeed seems better: output should be smaller, faster to run and it
avoids the ambiguity about missing config files.



-- 
Best Regards, Patrick Ohly

The content of this message is my personal opinion only and although
I am an employee of Intel, the statements I make here in no way
represent Intel's position on the issue, nor am I authorized to speak
on behalf of Intel on this matter.