iMX8 Yocto image with Fully Preemptible Kernel (RT) not available

Dear Toradex Experts,

I followed other thread for bitbaking a Yocto image for my Apalis-iMX8 module with PREEMPT_RT patchset enabled. I started with Toradex BSP3.0 :

$ repo init -u -b LinuxImage3.0 -m default.xml

And from your documentation about Real-Time Linux, I modified the conf/local.conf as below :

MACHINE ?= "apalis-imx8x"

# Use this distro
DISTRO = "tdx-x11"
DISTRO_mx8 = "tdx-xwayland-rt"


After bitbaking the qt5-x11-image, I checked by launching the kenel menuconfig, however I could select neither Preemptible Kernel (Basic RT) nor Fully Preemptible Kernel (RT) option since they are missing :

alt text

I would like to know if this is normal and what is the possible reason for NOT supporting these options, please ?

Thanks in advance and best regards,



You found a bug in the apalis-imx8x machine configuration. This machine currently does not apply the RT patch when the RT distro is chosen.

You could try to add the following line to the machine configuration:

PREFERRED_PROVIDER_virtual/kernel_preempt-rt = "linux-toradex-rt"

A patch to fix that is on its way into thud-next.

Using linux-toradex-rt will also configure using PREMPT_RT_FULL by default.

Thank you for reporting this.

Dear Max,

Thanks for your confirmation. I can see the patches are applied during bitbaking of kernel.