ptctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, addr, len, invalid_name) returns EFAULT rather than EINVAL under QEMU

[SteveLauC]

When I bump the CI Linux runner from Ubuntu 20.04 to 22.04, this test fails under QEMU for some architectures, it failed in this line:

failures:

---- test_prctl::test_set_vma_anon_name stdout ----
thread 'test_prctl::test_set_vma_anon_name' panicked at 'assertion failed: `(left == right)`
  left: `EFAULT`,
 right: `EINVAL`', test/sys/test_prctl.rs:149:9
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

failures:
    test_prctl::test_set_vma_anon_name

[asomers]

@devnexen do you know why this test fails on Ubuntu 22.04, or can you figure out?

[devnexen]

After trying, I can t make much sense of why it fails just because of a container update. Maybe update all but the cross-compiling part ?

[SteveLauC]

Maybe update all but the cross-compiling part ?

Ubuntu 20.04 will be eof in 2025, so we have to migrate to a new version:(

[devnexen]

would you consider trying a more advanced version just to see ? e.g. 23.04

[SteveLauC]

would you consider trying a more advanced version just to see ? e.g. 23.04

23.04 is not available, we have 24.04, though it is still in beta. Yeah, we can give it a try

[devnexen]

I barely see something else than that or ignoring the test on qemu.

[SteveLauC]

Yeah, we can give it a try

Tried it in this commit https://github.com/nix-rust/nix/pull/2417/commits/3ea403eda9ec6db0539f446a2f9efe085f38845a, no luck, looks like we have to ignore the test?

[SteveLauC]

Yeah, we can give it a try

Tried it in this commit 3ea403e, no luck, looks like we have to ignore the test?

Copy my comment to here:

I think we should still use Ubuntu 20.04 for that cross test as it won't harm anything until 20.04 is no longer available.

When 20.04 becomes deprecated, if this issue still exists, we will ignore it, or we can happily migrate to newer versions.