Modules doesn't autoload on runtime after custom build with default .config-wsl on version 6.6.87.2-microsoft-standard-WSL2

[nunorfidalgo]

Windows Version

Microsoft Windows [Version 10.0.26100.7462]

WSL Version

2.6.3.0

Are you using WSL 1 or WSL 2?

• WSL 2
• WSL 1

Kernel Version

6.6.87.2

Distro Version

Ubuntu 24.04.3 LTS

Other Software

No response

Repro Steps

Follow steps: https://learn.microsoft.com/en-us/community/content/wsl-user-msft-kernel-v6

1- Building the Microsoft Linux kernel v6.6.x

1. Open a WSL terminal window and launch the distro of your choice (for example: Ubuntu)
2. Clone the Microsoft Linux kernel repository from GitHub:
   git clone https://github.com/microsoft/WSL2-Linux-Kernel.git --depth=1 -b linux-msft-wsl-6.6.y
3. Install the required packages to build the kernel: sudo apt update && sudo apt install build-essential flex bison libssl-dev libelf-dev bc python3 pahole cpio
4. Change directory to the kernel source code: cd WSL2-Linux-Kernel
5. Build the kernel: make -j$(nproc) KCONFIG_CONFIG=Microsoft/config-wsl
6. Install the kernel modules and headers: sudo make modules_install headers_install
7. Copy the kernel image to the Windows file system: cp arch/x86/boot/bzImage /mnt/c/
8. Exit the WSL terminal window

2 - Installing the Microsoft Linux kernel v6.6.x

1. Create or edit the file %USERPROFILE%.wslconfig with the following: [wsl2] kernel=C:\\bzImage
2. Open a PowerShell terminal window as Administrator
3. Stop the WSL instance: wsl --shutdown

3 - Using the Microsoft Linux kernel v6.6.x

1. Open a WSL terminal window and launch the distro of your choice (for example: Ubuntu): uname -r
2. You should see the following output: 6.6.x-WSL2-Microsoft

Expected Behavior

On a clean boot with kernel version 6.6.87.2-microsoft-standard-WSL2 the list of modules is this:
Module Size Used by
xfrm_user 49152 1
xfrm_algo 16384 1 xfrm_user
xt_set 20480 0
ip_set 49152 1 xt_set
xt_addrtype 12288 4
xt_CHECKSUM 12288 1
xt_MASQUERADE 16384 5
xt_conntrack 12288 3
ipt_REJECT 12288 2
nf_reject_ipv4 12288 1 ipt_REJECT
nft_compat 16384 15
intel_rapl_msr 16384 0
intel_rapl_common 32768 1 intel_rapl_msr
kvm_intel 356352 0
crc32c_intel 16384 0
battery 20480 0
ac 16384 0
kvm 970752 1 kvm_intel
irqbypass 12288 1 kvm
sch_fq_codel 16384 1
configfs 53248 1
autofs4 45056 0
br_netfilter 28672 0
bridge 282624 1 br_netfilter
stp 12288 1 bridge
llc 12288 2 bridge,stp
ip_tables 28672 0
tun 53248 0

Actual Behavior

On a clean boot with kernel version 6.6.87.2-microsoft-standard-WSL2+ the list of modules is this:
Module Size Used by
intel_rapl_msr 16384 0
intel_rapl_common 36864 1 intel_rapl_msr
kvm_intel 385024 0
crc32c_intel 16384 0
battery 24576 0
ac 16384 0
kvm 1183744 1 kvm_intel
irqbypass 12288 1 kvm
configfs 61440 1
ip_tables 32768 0
autofs4 53248 0

And then for some network stuff I need to work like bridge and qemu_br modules I have to load this list of modules manually or by script:
##############
#!/bin/bash
modules="
garp
8021q
tun
br_netfilter

kvm_intel
crc32c_intel
sch_fq_codel

ip_tables
nf_nat
nf_tables
nft_compat
ipt_REJECT
nf_reject_ipv4
ip_set
xt_set
xfrm_user

xt_addrtype
xt_conntrack
xt_MASQUERADE
xt_mark
xt_comment
xt_multiport
xt_CHECKSUM
"

for m in $modules; do
echo "Loading module: $m"
sudo modprobe $m
done
################

Another error is: extension masquerade revision 0 not supported, missing kernel module if proper module is not loaded.

Diagnostic Logs

No response

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