Running Arm binaries on x86 with binfmt-misc and qemu
Here’s how to set up Debian (and probably Ubuntu) to run a armhf binary.
Install and configure
sudo dpkg --add-architecture armhf
sudo apt update
sudo apt install libc6:armhf qemu-user-static
sudo ln -s / /etc/qemu-binfmt/arm
The symlink should point to the location of the elf interpreter and is passed
as the -L argument to qemu. The binfmt-misc setup uses /etc/qemu-binfmt/%M
where %M is the machine name.
Test it out
Test it out by building a C program and running it.
$ echo -e '#include <stdio.h>\nint main() {printf("Hello, World!\\n");}' > hello.c
$ arm-linux-gnueabihf-gcc -o hello{,.c}
$ file hello
hello: ELF 32-bit LSB pie executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-armhf.so.3, BuildID[sha1]=5dd9005818049bb8b57d7b38bfc05568945638f6, for GNU/Linux 3.2.0, not stripped
$ ./hello
Hello, World!
Other libraries
Install libraries as you would for native packages. Here’s an example of using openssl:
sudo apt install libssl-dev:armhf
#include <openssl/rand.h>
int main()
{
unsigned char buffer[8];
RAND_bytes(buffer, sizeof(buffer));
for (int i = 0; i < sizeof(buffer); i++)
printf("%02x ", buffer[i]);
printf("\n");
}
$ gcc -o random{,.c} -lcrypto
$ ./random
b3 ba b9 34 fe 20 99 69
$ arm-linux-gnueabihf-gcc -o random{,.c} -lcrypto
$ ./random
e4 6b 2f 47 47 80 fa 9d
Notes
Third party repos
Third party repositories are unlikely to have metadata for the foreign
architecture, resulting this warning when running apt update:
N: Skipping acquire of configured file 'main/binary-armhf/Packages' as repository 'https://packages.riot.im/debian default InRelease' doesn't support architecture 'armhf'
We can tell apt a repository only supports a given architecture by adding
arch=amd64 (or whatever your native arch is) to the
/etc/apt/sources.list.d/ config:
deb [signed-by=/usr/share/keyrings/riot-im-archive-keyring.gpg arch=amd64] https://packages.riot.im/debian/ default main
As space can be used if there’s already an option there.
Ports
If you’re on Ubuntu and trying to use an architecture that is hosted on the
ports mirror instead of the main mirror, such as ppc64el, you will need an
extra step before running apt update:
sudo sed -i -e 's/deb http/deb [arch=amd64] http/g' /etc/apt/sources.list
sudo dd of=/etc/apt/sources.list.d/ppc64el.list <<EOF
deb [arch=ppc64el] http://ports.ubuntu.com/ $release main universe restricted"
deb [arch=ppc64el] http://ports.ubuntu.com/ $release-updates main universe restricted"
EOF
This marks the existing repos as amd64 only, and adds the ports mirror for ppc64el only. This is not required on Debian, as ppc64el is hosted in the main mirror.
Thanks to Jeremy for the sed and dd oneliners. They’re used in the libnvme CI.