Re: [PATCH] selftests/damon/sysfs.py: clean up sh processes used for obsolete_target test

[SJ Park <sj@kernel.org>]

Hello Hari,

On Tue, 21 Jul 2026 21:04:04 +0200 Hari Mishal <harimishal1@gmail.com> wrote:

> The obsolete_target test spawns three sh processes and uses their pids
> as DAMON monitoring targets.  These processes are created without their
> own stdin, so they inherit the test program's stdin, and they are never
> waited on or told to exit.  As a result, they are left running (or
> become zombies) as orphaned children after the test program exits.

Thank you for finding this problem and sharing this great patch!

> 
> Give each sh process its own dedicated stdin pipe instead of inheriting
> the test program's, and after the targets are no longer needed,
> communicate() with each process to close its stdin.  This sends EOF to
> the shell, which makes it exit, and communicate() then reaps the
> process.

Can't we use terminate() or kill() instead of communicate()?


Thanks,
SJ

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