Enable cross-architecture builds

[d2r4]

Using multiarch/qemu-user-static allows for many cross-architecture build scenarios. In this case looking to enable builds of the arm32v7 and arm64v8 images on common amd64 platforms such as docker hubs build infrastructure.

[adamradocz]

The docker hub doesn't build the images for free for open-source projects anymore, so I don't know how this PR will help us build ARM images.

Is there a way to modify the https://github.com/BOINC/boinc-client-docker/blob/master/update.sh file in order to do that on any local machine?

[d2r4]

Yes, this can be added to update.sh. Though I am not sure yet how to clean-up afterwards. Once qemu-user-static runs the effects seem to stick around until reboot.

[adamradocz]

Got this error:

root@Development:~/boinc-client-docker# docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
Unable to find image 'multiarch/qemu-user-static:latest' locally
latest: Pulling from multiarch/qemu-user-static
19d511225f94: Pull complete 
6a33d6a40b9b: Pull complete 
30abb83a18eb: Pull complete 
0657daef200b: Pull complete 
32680003bcd0: Pull complete 
Digest: sha256:0803de73e3799a381acdd48f73516046f066a7bc121ed000d447f65276758a3c
Status: Downloaded newer image for multiarch/qemu-user-static:latest
mount: permission denied (are you root?)
mount: permission denied (are you root?)

[d2r4]

Running that command in a fresh install of Ubuntu 22.04 LTS, Docker 20.10.17. I am not receiving an error. Can you provide some info about your build environment so I can attempt to reproduce this issue?

d2r4@d2r4-VirtualBox:~$ sudo docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
Unable to find image 'multiarch/qemu-user-static:latest' locally
latest: Pulling from multiarch/qemu-user-static
19d511225f94: Pull complete 
6a33d6a40b9b: Pull complete 
30abb83a18eb: Pull complete 
0657daef200b: Pull complete 
32680003bcd0: Pull complete 
Digest: sha256:0803de73e3799a381acdd48f73516046f066a7bc121ed000d447f65276758a3c
Status: Downloaded newer image for multiarch/qemu-user-static:latest
Setting /usr/bin/qemu-alpha-static as binfmt interpreter for alpha
Setting /usr/bin/qemu-arm-static as binfmt interpreter for arm
Setting /usr/bin/qemu-armeb-static as binfmt interpreter for armeb
Setting /usr/bin/qemu-sparc-static as binfmt interpreter for sparc
Setting /usr/bin/qemu-sparc32plus-static as binfmt interpreter for sparc32plus
Setting /usr/bin/qemu-sparc64-static as binfmt interpreter for sparc64
Setting /usr/bin/qemu-ppc-static as binfmt interpreter for ppc
Setting /usr/bin/qemu-ppc64-static as binfmt interpreter for ppc64
Setting /usr/bin/qemu-ppc64le-static as binfmt interpreter for ppc64le
Setting /usr/bin/qemu-m68k-static as binfmt interpreter for m68k
Setting /usr/bin/qemu-mips-static as binfmt interpreter for mips
Setting /usr/bin/qemu-mipsel-static as binfmt interpreter for mipsel
Setting /usr/bin/qemu-mipsn32-static as binfmt interpreter for mipsn32
Setting /usr/bin/qemu-mipsn32el-static as binfmt interpreter for mipsn32el
Setting /usr/bin/qemu-mips64-static as binfmt interpreter for mips64
Setting /usr/bin/qemu-mips64el-static as binfmt interpreter for mips64el
Setting /usr/bin/qemu-sh4-static as binfmt interpreter for sh4
Setting /usr/bin/qemu-sh4eb-static as binfmt interpreter for sh4eb
Setting /usr/bin/qemu-s390x-static as binfmt interpreter for s390x
Setting /usr/bin/qemu-aarch64-static as binfmt interpreter for aarch64
Setting /usr/bin/qemu-aarch64_be-static as binfmt interpreter for aarch64_be
Setting /usr/bin/qemu-hppa-static as binfmt interpreter for hppa
Setting /usr/bin/qemu-riscv32-static as binfmt interpreter for riscv32
Setting /usr/bin/qemu-riscv64-static as binfmt interpreter for riscv64
Setting /usr/bin/qemu-xtensa-static as binfmt interpreter for xtensa
Setting /usr/bin/qemu-xtensaeb-static as binfmt interpreter for xtensaeb
Setting /usr/bin/qemu-microblaze-static as binfmt interpreter for microblaze
Setting /usr/bin/qemu-microblazeel-static as binfmt interpreter for microblazeel
Setting /usr/bin/qemu-or1k-static as binfmt interpreter for or1k
Setting /usr/bin/qemu-hexagon-static as binfmt interpreter for hexagon

[adamradocz]

Freshly installed Ubuntu 20.04 on LXC container.

[d2r4]

I setup Ubuntu 20.04.5 LTS hosting a matching privileged LXC container, the container is running docker 20.10.18. In this environment I am still able to run that docker command successfully and don't see the "mount: permission denied (are you root?)" errors. Do you have any other information that could be helpful as to your setup?