cross-built kernel cannot load externally-built modules

[classabbyamp]

System Info

Void 6.8.12_2 aarch64-glibc

Package(s) Affected

linux6.8 at minimum, probably other linux6.* kernels (rpi-kernel is not affected)

if the kernel is built natively, this issue does not occur

Expected behaviour

externally-built (dkms or other mechanism) modules load successfully

nm --print-size --size-sort hello.ko | grep __this_module       
0000000000000000 0000000000000500 D __this_module

Actual behaviour

# modprobe ./hello.ko
modprobe: ERROR: could not insert 'hello': Exec format error

dmesg:

[...] module hello: .gnu.linkonce.this_module section size must match the kernel's built struct module size at run time

nm --print-size --size-sort hello.ko | grep __this_module
0000000000000000 00000000000004c0 D __this_module

Steps to reproduce

mkdir -p hello-mod && cd hello-mod

cat <<EOF > Makefile 
obj-m += hello.o

PWD := $(CURDIR)

all:
	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules

clean:
	make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
EOF

cat <<EOF > hello.c
#include <linux/module.h>
#include <linux/printk.h>

int init_module(void) {
    pr_info("hello");
    return 0;
}

void cleanup_module(void) {
    pr_info("goodbye");
}

MODULE_LICENSE("GPL");
EOF

make
sudo modprobe ./hello.ko

Notes

Error message introduced by https://lore.kernel.org/lkml/[email protected]/T/