crun tries to use pidfd on old kernels

[mbien]

since I updated crun from 0.14 to 0.15 on debian stable (using podman from testing repo), podman is throwing errors when i stop a container.

example:

podman run --runtime /usr/bin/crun --rm docker.io/library/alpine cat etc/os-release
NAME="Alpine Linux"
ID=alpine
VERSION_ID=3.12.1
PRETTY_NAME="Alpine Linux v3.12"
HOME_URL="https://alpinelinux.org/"
BUG_REPORT_URL="https://bugs.alpinelinux.org/"
2020-10-27T18:43:50.000455481Z: open pidfd: Function not implemented
2020-10-27T18:43:50.000535319Z: open pidfd: Function not implemented
ERRO[0000] delete container: error removing container 38618f35f94b82e2c2932280773bbb68bb271a7b2d053da9a71571587dc4b677 from runtime: `/usr/bin/crun delete --force 38618f35f94b82e2c2932280773bbb68bb271a7b2d053da9a71571587dc4b677` failed: exit status 1 
ERRO[0000] Error removing container 38618f35f94b82e2c2932280773bbb68bb271a7b2d053da9a71571587dc4b677: error cleaning up container 38618f35f94b82e2c2932280773bbb68bb271a7b2d053da9a71571587dc4b677: error removing container 38618f35f94b82e2c2932280773bbb68bb271a7b2d053da9a71571587dc4b677 from runtime: `/usr/bin/crun delete --force 38618f35f94b82e2c2932280773bbb68bb271a7b2d053da9a71571587dc4b677` failed: exit status 1 

latest kernel from debian stable:

uname -a
Linux virtualdebian 4.19.0-12-amd64 #1 SMP Debian 4.19.152-1 (2020-10-18) x86_64 GNU/Linux

upgrading the kernel or downgrading crun to 0.14 fixes it. According to the error msg, it looks like crun attempts to use pidfd_open() which is a 5.3+ kernel feature (https://man7.org/linux/man-pages/man2/pidfd_open.2.html).

[giuseppe]

it is fixed with: #520

Would it be possible for you to verify if the current development version works? If that helps, I can cut a new release

[mbien]

sure i could test it in a VM. Binaries would be great.

[giuseppe]

there is a static binary generated in the PR Artifacts: https://github.com/containers/crun/runs/1255158523

[mbien]

podman run --runtime /home/mbien/crun-linux-amd64 --rm docker.io/library/alpine cat etc/os-release
NAME="Alpine Linux"
ID=alpine
VERSION_ID=3.12.1
PRETTY_NAME="Alpine Linux v3.12"
HOME_URL="https://alpinelinux.org/"
BUG_REPORT_URL="https://bugs.alpinelinux.org/"

worked fine

[giuseppe]

thanks for confirming it!

[mbien]

@giuseppe any ETA for the next crun release which would include this fix for the regression?

[giuseppe]

I can cut a release in the next days.

@rhatdan are you fine with merging #527?

[rhatdan]

Merged.

[giuseppe]

@mbien the new release is out: https://github.com/containers/crun/releases/tag/0.15.1

[mbien]

@giuseppe awesome, thanks!