qemu-user-static

> Using wrappers doesn't really help that much because the difficulties are in the things that aren't covered anyway. Proot doesn't help for these issues, there's a long-standing open issue for that one. Could I ask for more details? I could certainly believe that podman doesn't do something that's needed, but I'm pretty sure it does everything that this particular article spends time setting up out of the box. And I can't find anything about proot; https://gitlab.postmarketos.org/postmarketOS/pmbootstrap/-/i... gives me nothing and a web search only gives me https://gitlab.com/postmarketOS/pmbootstrap/-/issues/2052#no... which is... either they're wrong (because faking mounts is definitely something proot does), they were right but it's changed (I don't know when that was added), or I'm misunderstanding the problem (maybe pmbootstrap dyn

and its "oh, you want multi-arch, do you?" friend. While prosecuting this <https://gitlab.com/gitlab-org/gitlab/-/issues/339567> I learned that they bundle binfmt into the buildkit docker image <https://github.com/moby/buildkit/blob/v0.12.5/Dockerfile#L11...> which itself is compiled against a static copy of qemu <https://github.com/tonistiigi/binfmt/blob/deploy/v6.2.0-26/D...> with various /proc/sys/fs/binfmt_misc wizardry <https://github.com/tonistiigi/binfmt/blob/deploy/v6.2.0-26/c...> We ended up switching to using multiarch/qemu-user-static:7.2.0-1 <https://hub.docker.com/layers/multiarch/qemu-user-static/7.2...> which also mutates binfmt_misc in buildx's context in order to exec the static copy of qemu in it but I find their shell script much more legible about what's going on: <https://github.com/multiarch/qemu-user-static/blob/v7.

Another great tool for cross arch development is qemu-static-user. It allows you to run your nonnative architecture docker images on host using a qemu container for translation and only requires about one command to get working. It’s life saving for me when I need to test but setting up a full VM or native server is too time consuming. https://github.com/multiarch/qemu-user-static

> binfmt_misc https://en.wikipedia.org/wiki/Binfmt_misc > binfmt_misc can also be combined with QEMU to execute programs for other processor architectures as if they were native binaries.[9] QEMU supported [ARM guest] machines: https://wiki.qemu.org/Documentation/Platforms/ARM#Supported_... Edit: from "Running and Building ARM Docker Containers on x86" (which also describes how to get CUDA working) https://www.stereolabs.com/docs/docker/building-arm-containe... : sudo apt-get install qemu binfmt-support qemu-user-static # Install the qemu packages docker run --rm --privileged multiarch/qemu-user-static --reset -p yes # Execute the registering scripts docker run --rm -t arm64v8/ubuntu uname -m # Test the emulation environment https://github.com/multiarch/qemu-user-static : > multiarch/qemu-user-static is to enable an execution of d

(5) Docker Image (amd64) ^ | (4) QEMU Binfmt (arm64 <-> amd64 binary emulation layer) ^ | (3) Linux VM (arm64) ^ | (2) Hypervisor.framework (arm64, macOS native virtualization framework) ^ | (1) Docker for Mac Linux Kernel has a feature to allow using a wrapper to execute userspace program based on file header (binfmt[1]). In this case, Linux VM in (3) has QEMU user mode emulation registered as binfmt, so any amd64 binaries are automatically wrapped into `qemu-x86_64-static /path/to/bin` and run. Docker Image itself doesn't run a Linux kernel but use one from the VM host, so this scenario is possible. This is also how multiarch[2] works (for amd64 to arm64/ppc64le/etc.

From their roadmap, it does not appear they have really investigated this yet. [1] Rosetta 2 translates Mac apps and can deal with JIT, but I do not believe it will work through virtualization. It should be relatively light lifting to make Docker for Mac run an ARM linux installation and ARM-built containers. From there, you likely would want to strategically add multi-arch container support to the docker runtime. This might be implemented based on existing qemu containers [2] 1: https://github.com/docker/roadmap/issues/142 2: https://github.com/multiarch/qemu-user-static

I'm using https://github.com/multiarch/qemu-user-static - that's what it is, right ?

I'm using it extensively, but as a build tool: https://github.com/multiarch/qemu-user-static (See https://taoofmac.com/space/blog/2019/04/21/2300 and https://github.com/insightfulsystems/alpine-python)