Linux Image Fails for Certain Targets Due to Migration from Kernel 5.x to 6.x

[Alexhuszagh]

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• I've looked through the issues and pull requests for similar reports

Describe your issue

Builds for certain images, such as sparc64-unknown-linux-gnu, have failed due to a failure to find candidate kernel install versions in the latest repositories. This causes wildcard expansion to fail, which then means max_kernel_version is called with no suitable candidates: an empty string.

The offending lines are of the following:

powerpc64)
    # there is no stable port
    arch=ppc64
    # https://packages.debian.org/en/sid/linux-image-powerpc64
    kernel='5.*-powerpc64'
    debsource="deb http://ftp.ports.debian.org/debian-ports unstable main"
    debsource="${debsource}\ndeb http://ftp.ports.debian.org/debian-ports unreleased main"
    # sid version of dropbear requires these dependencies
    deps=(libcrypt1:"${arch}")
    ;;
riscv64)
    kernel="5.*-riscv64"
    debsource="deb http://ftp.ports.debian.org/debian-ports unstable main"
    debsource="${debsource}\ndeb http://ftp.ports.debian.org/debian-ports unreleased main"
    deps=(libcrypt1:"${arch}")
    ;;
sparc64)
    # there is no stable port
    # https://packages.debian.org/en/sid/linux-image-sparc64
    kernel='5.*-sparc64'
    debsource="deb http://ftp.ports.debian.org/debian-ports unstable main"
    debsource="${debsource}\ndeb http://ftp.ports.debian.org/debian-ports unreleased main"
    # sid version of dropbear requires these dependencies
    deps=(libcrypt1:"${arch}")
    ;;

Changing all wildcards to accept 5.x or 6.x should fix this issue.

What target(s) are you cross-compiling for?

powerpc64-unknown-linux-gnu, riscv64gc-unknown-linux-gnu, sparc64-unknown-linux-gnu

Which operating system is the host (e.g computer cross is on) running?

• macOS
• Windows
• Linux / BSD
• other OS (specify in description)

What architecture is the host?

• x86_64 / AMD64
• arm32
• arm64 (including Mac M1)

What container engine is cross using?

• docker
• podman
• other container engine (specify in description)

cross version

cross 0.2.4 (e23ef05)

Additional information / notes

This will be a breaking change, but it's unavoidable really. Luckily, we're in the middle of migrating from 0.2.4 to 0.3.0, so a breaking change is acceptable.