All, With Hugo's help, I've figured out how to compile kernel modules for camkes-vm-linux. I've written up the procedure here: https://github.com/NeisesResearch/kernel_module_workstation/wiki/seL4Config and I've partially automated it here: https://github.com/NeisesResearch/kernel_module_workstation I'm happy to receive any feedback, and I hope this makes someone's life a bit easier. Cheers, Michael Neises On Sun, Jul 11, 2021 at 6:23 PM Hugo V.C. wrote:

Hi Michael,

in my specific case (qemu-arm-virt) I got the linux kernel config and symbols from the linux kernel folder that allowed me to compile custom kernel version and from there I could compile custom module and my custom kernel. When I tried to just compile a module for the provided kernel it didn't worked for me. Think that you do not have control on what compiler/environment has been used to generate the kernel binary provided in the tutorials...

My suggestion is you download the latest version of kernel 4.9, import .config and symbols file of the current kernel, and first compile your own linux kernel from scratch and in a separe step. Then overwrite the old kernel image with your custom image and then change the path of the new kernel sources in the .build file so the modules can compile correctly.

Hope it helps. Don't hesitate to contact me privately so I can try to help you and so you can document it as I agree this is really required..

El lun., 12 jul. 2021 0:26, Michael Neises escribió:

...

Hello all,

I recently spent a lot of time getting the camkes-vm-linux tutorial to work, because it is the only example I could find of compiling a kernel module for the linux vm as a part of the camkes build process. Unfortunately, the kernel module doesn't seem to work. For more information, see the previous email chain as well as

https://github.com/NeisesResearch/vm_measure/wiki/Building-the-camkes_vm_lin... .

In lieu of doing things the right way, I believe I could compile a kernel module for the linux kernel that is provided as part of the camkes build system. I believe this is how the introspect-app accomplishes its work. However, I need to have the exact kernel and exact configuration in order to compile the kernel module correctly.

Can anyone point me to the correct kernel version and configuration, so that I can target the provided linux kernel for module compilation?

Or if there's a better way to get a kernel module in there, please let me know.

Cheers, Michael Neises _______________________________________________ Devel mailing list -- devel@sel4.systems To unsubscribe send an email to devel-leave@sel4.systems

Michael Neises wrote:

All,

With Hugo's help, I've figured out how to compile kernel modules for camkes-vm-linux. I've written up the procedure here: https://github.com/NeisesResearch/kernel_module_workstation/wiki/seL4Config and I've partially automated it here: https://github.com/NeisesResearch/kernel_module_workstation

I'm happy to receive any feedback, and I hope this makes someone's life a bit easier.

Cheers, Michael Neises

On Sun, Jul 11, 2021 at 6:23 PM Hugo V.C. <skydivebcn(a)gmail.com> wrote:

...

Hi Michael,

in my specific case (qemu-arm-virt) I got the linux kernel config and symbols from the linux kernel folder that allowed me to compile custom kernel version and from there I could compile custom module and my custom kernel. When I tried to just compile a module for the provided kernel it didn't worked for me. Think that you do not have control on what compiler/environment has been used to generate the kernel binary provided in the tutorials...

My suggestion is you download the latest version of kernel 4.9, import .config and symbols file of the current kernel, and first compile your own linux kernel from scratch and in a separe step. Then overwrite the old kernel image with your custom image and then change the path of the new kernel sources in the .build file so the modules can compile correctly.

Hope it helps. Don't hesitate to contact me privately so I can try to help you and so you can document it as I agree this is really required..

El lun., 12 jul. 2021 0:26, Michael Neises <neisesmichael(a)gmail.com> escribió:

Hello all,

I recently spent a lot of time getting the camkes-vm-linux tutorial to work, because it is the only example I could find of compiling a kernel module for the linux vm as a part of the camkes build process. Unfortunately, the kernel module doesn't seem to work. For more information, see the previous email chain as well as

https://github.com/NeisesResearch/vm_measure/wiki/Building-the-camkes_vm_li… .

In lieu of doing things the right way, I believe I could compile a kernel module for the linux kernel that is provided as part of the camkes build system. I believe this is how the introspect-app accomplishes its work. However, I need to have the exact kernel and exact configuration in order to compile the kernel module correctly.

Can anyone point me to the correct kernel version and configuration, so that I can target the provided linux kernel for module compilation?

Or if there's a better way to get a kernel module in there, please let me know.

Cheers, Michael Neises _______________________________________________ Devel mailing list -- devel(a)sel4.systems To unsubscribe send an email to devel-leave(a)sel4.systems

Hi Michael and all, I'm writing in the mailing list to maintain the history of the issue since I encountered the same situation. Version mismatch is: "4.8.16 SMP mod_unload 686" in the module VS. "4.8.16 mod_unload 686" in the kernel. The fastest way to solve it (to ones who is running the tutorial right now) is to use kernel config file "config.backup-singlecore" from the same repository to compile "non-SMP" module. It can be done by replacing line: set(linux_config "${CAMKES_VM_LINUX_DIR}/linux_configs/${linux_major}.${linux_minor}/32/config") with set(linux_config "${CAMKES_VM_LINUX_DIR}/linux_configs/${linux_major}.${linux_minor}/32/config.backup-singlecore") in CMakeList.txt (tutorial directory camkes-vm-linuxyyy). I have reported the diagnosis in the issue #80 in sel4-tutorials. Thanks Nataliya