Bug#981219: schroot overwrites cpuset

[Roger Leigh <rleigh@codelibre.net>]

On 27 Jan 2021, at 20:39, David Bremner <bremner@debian.org> wrote:
> 
> Package: schroot
> Version: 1.6.10-11+b1
> Severity: normal
> 
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> Hash: SHA256
> 
> As you can see with session below, schroot throws away the processor
> affinities present in the parent process.  This breaks a common
> strategy (used e.g. by slurm) for sharing multi-processor machines.

We don’t actively do anything within schroot to change this, so it must be a side-effect of some action it takes during session setup.

The main actions under our control are basic fork/chroot/setuid/setgid/exec and I doubt these are responsible.

The PAM auth and session handling is I think the most likely culprit, and this is not under our direct control.  Is there a particular PAM module which can change these cpusets?  If so, can you edit the schroot PAM configuration and see if it can be disabled this way?  Possibly in @common-session?


Thanks,
Roger