Support linux/loong64 Arch

[dongjiang1989]

Description

Add support for loong64 builds.

Motivation and Context

To be able to build binaries for loong64.

How to test this PR?

Link: golang/go#46229

[xen0n]

It seems a bit involved to add such support. We have to:

• bump https://github.com/tonistiigi/xx toolchain components to very recent versions (binutils 2.40+, Clang 16+, go 1.19+ but ideally the next version that's go1.21.0), and
• ideally bump the QEMU version to 8.0+

before doing the trivial additions. (Which may or may not be so, depending on the tools involved.)

[emmansun]

After #151 #174 , Why is there still no linux/loong64 image? missing one platform in https://github.com/tonistiigi/binfmt/blob/master/docker-bake.hcl ?

target "all-arch" {
  platforms = [
    "linux/amd64",
    "linux/arm64",
    "linux/arm/v6",
    "linux/arm/v7",
    "linux/ppc64le",
    "linux/s390x",
    "linux/riscv64",
    "linux/386",
  ]
}

@tonistiigi @yzewei @vicamo

[xen0n]

After #151 #174 , Why is there still no linux/loong64 image? missing one platform in https://github.com/tonistiigi/binfmt/blob/master/docker-bake.hcl ?

You could use a little patience or make it happen yourself ;-) LoongArch availability is a bit limited especially outside of China, and open-source projects like this usually are severely limited in manpower, so you cannot expect people to keep their eyes on LoongArch at all times.

I'll try adding the support in a few days. If you see a PR fixing this issue, that'd be it, or I'll post on why this is still not feasible at the moment ;-)

[yzewei]

After #151 #174 , Why is there still no linux/loong64 image? missing one platform in https://github.com/tonistiigi/binfmt/blob/master/docker-bake.hcl ?

You could use a little patience or make it happen yourself ;-) LoongArch availability is a bit limited especially outside of China, and open-source projects like this usually are severely limited in manpower, so you cannot expect people to keep their eyes on LoongArch at all times.

I'll try adding the support in a few days. If you see a PR fixing this issue, that'd be it, or I'll post on why this is still not feasible at the moment ;-)

@xen0n Thanks!
It is better to wait for the alpine community to support loongarch before submitting a similar PR, otherwise it will be different from other architectures and bring additional code maintenance burden

[yzewei]

After #151 #174 , Why is there still no linux/loong64 image? missing one platform in https://github.com/tonistiigi/binfmt/blob/master/docker-bake.hcl ?

target "all-arch" {
  platforms = [
    "linux/amd64",
    "linux/arm64",
    "linux/arm/v6",
    "linux/arm/v7",
    "linux/ppc64le",
    "linux/s390x",
    "linux/riscv64",
    "linux/386",
  ]
}

@tonistiigi @yzewei @vicamo

@emmansun As I said earlier, if you currently need to use a loongarch-based binfmt image, https://lcr.loongnix.cn

[xen0n]

It seems tonistiigi/xx needs to get LoongArch awareness: the xx-info helper currently does not handle the loongarch64 loong64 things, which it definitely needs to. And the fact that the Alpine arch names are recorded means we'd better wait until things settle at Alpine side -- at least the architecture name needs to be frozen. The Alpine arch name seems to be loongarch64 already -- consistent with a Loongson first-party effort.

[xen0n]

It seems tonistiigi/xx needs to get LoongArch awareness: the xx-info helper currently does not handle the loongarch64 loong64 things, which it definitely needs to.

This doesn't affect non-loong64-host builds -- it is used to exclude the *-linux-user configuration corresponding to the host arch, but we're primarily concerned with having loong64 emulation on other hosts e.g. amd64 or arm64. I've made #186 to hopefully fix this issue.