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charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, 2026-01-28 at 14:41 +0100, Andrea Righi wrote: > Just to make sure we're testing the same thing, I'm currently using > https://git.kernel.org/pub/scm/linux/kernel/git/arighi/linux.git, > branch > scx-dl-server. >=20 > I'm running this test inside virtme-ng: > =C2=A0 $ vng -vb --config tools/testing/selftests/sched_ext/config > =C2=A0 $ vng -v -- tools/testing/selftests/sched_ext/runner -t rt_stall Well, that's a fun one, I could reproduce the same failure you described in vng on another x86 box. The arm box (bare metal) I used initially still passes just fine all 4 iterations of the test. On the x86 box (vng) I tried different orders of iterations (where the original is fair-ext-fair-ext) with and without the ext server active. No ext-server: the ext iteration fails and breaks also fair (unlike the arm64 box where the fair was intact) ext-server active: a sequence fair-ext breaks both (like you observe). I don't have time to look further into this right now, but it looks like an interesting pattern. Thanks, Gabriele