Error in Section "sysfs_volume" during Yocto build WP76xx

Hi, I am trying to build Linux Kernel 4.14.253 based on the Release R17 for the WP76xx module. In the process, we are adding some custom recipes and files to the OS. But during the build, I’m getting the following error related to the size of rootfs.4k.ubifs.

To resolve this, I changed UBI_ROOTFS_SIZE ?= “48MiB” in the file yocto/meta-swi/meta-swi-mdm9x28/conf/machine/swi-mdm9x28.conf which was 42MiB before. The image was built successfully, but there are some issues related to “Space running out” and it reboots due to this space issue.

I am looking for a way to reduce the size of this rootfs.4k.ubifs by at least 300Kb to successfully build the image.

will you consider to put some libraries in RAM?

Or you can consider to put some libraries in userapp partition like /home/root:

Or you can check if there is some driver you don’t need in ./kernel/arch/arm/configs/mdm9607_defconfig

Thank you @jyijyi . I will try these.

Hi @jyijyi . This is my config file. I am not sure which all drivers I can remove from here. It looks like a minimal configuration file.
mdm9607_defconfig (10.6 KB)

you can also use menuconfig to know which driver you need:

Probably it will rewrite the mdm9607_defconfig for you

I ran bitbake -c menuconfig virtual/kernel and removed sound card support.

And then ran bitbake mdm9x28-image-minimal and ended up with another error.

What is the correct way to remove certain packages ? for instance I wanted to remove alsa from kernel.

will you consider to put some libraries in RAM?

Or you can consider to put some libraries in userapp partition like /home/root:

I don’t want to do too many modifications. As I can see that there is hardly a 300KB difference between the volume and the actual image. I just wanted to remove a few components from the image, so that the image size reduces. Alsa is audio related and in my application, there is no need for any audio functions. So can you please give some guidance on how to remove these components from the image during yocto build?

if you are not using bluetooth or wifi, you might see if there is anything that can be removed

./meta-swi/meta-swi-mdm9x28/recipes-core/images/mdm9x28-image.inc
OR
./kernel/arch/arm/configs/mdm9607_defconfig
OR
menuconfig

I tried, but no luck. Wifi is already disabled.
mdm9x28-image.inc (7.2 KB)

What is the standard process to list and remove components from the Linux kernel while building the image in Yocto?

How about disable bluetooth or wifi in menuconfig

It is already disabled.

any drive you don’t need in menuconfig?
I think you need to do some trial experiment

In the menuconfig, I disabled the following options

Verbose BUG() reporting (adds 70K)
Enable stack unwinding support (EXPERIMENTAL)
PowerPC BCJ filter decoder
Remote Controller support

And then I rebuilt the image just now, however, I don’t see any changes in the total image size.

is it the same for clean build?

make clean
make

Hey @jyijyi, I found the solution.

  1. First list all the packages/recipes using bitbake-layers show-recipes

You’ll see something like this

  1. You can use the package’s name in the conf/local.conf to remove them from the build
    using IMAGE_INSTALL_remove

image

With these changes, I was able to build the image without the “sysfs_volume” error.

Thank you @jyijyi for all the suggestions. :slight_smile:

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