Adding to your local.conf right out of the gate:
EXTRA_IMAGE_FEATURES = "read-only-rootfs"
while you are trying to sort out other things can be just another
complication to an already steep learning curve.
For example, I found simply enabling this with systemd caused:
systemd[1]: Failed to fork off sandboxing environment for executing generators: Protocol error
[!!!!!!] Failed to start up manager.
systemd[1]: Freezing execution.
While I'd like to get to the root cause of that, it doesn't change that
things boot fine w/o adding to EXTRA_IMAGE_FEATURES, even though the
rootfs is still read-only courtesy of dm-verity.
Reword things so as to make it clear it isn't strictly a hard requirement
and hence can be delayed as people work through their implementation.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
Some platform creators tend to list a whole bunch of layers by
default in conf/bblayers.conf. Without getting into the debate of
whether that is a good idea, it can tend to have the effect of
people seeing the meta-security DISTRO_FEATURES warning time and
time again and becoming essentially numb to it.
After having fallen into this trap myself, I figured it was worth
the extra mention in the dm-verity doc so there is a better chance
of users realizing "hey - this applies to me!".
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
As things stand currently, the only way to learn about the Yocto
specific settings for implementing dm-verity is by reading the source.
Here we try and capture some of the basic information that exists
out there in mailing list posts and get that in-tree.
Board specific settings/tips will be stored in board specific files.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
