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charset=us-ascii Content-Disposition: inline In-Reply-To: <20251017093214.70029-5-arighi@nvidia.com> Hi! On 17/10/25 11:25, Andrea Righi wrote: > From: Joel Fernandes > > Hotplugged CPUs coming online do an enqueue but are not a part of any > root domain containing cpu_active() CPUs. So in this case, don't mess > with accounting and we can retry later. Without this patch, we see > crashes with sched_ext selftest's hotplug test due to divide by zero. > > Signed-off-by: Joel Fernandes > --- > kernel/sched/deadline.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c > index 4aefb34a1d38b..f2f5b1aea8e2b 100644 > --- a/kernel/sched/deadline.c > +++ b/kernel/sched/deadline.c > @@ -1665,7 +1665,12 @@ int dl_server_apply_params(struct sched_dl_entity *dl_se, u64 runtime, u64 perio > cpus = dl_bw_cpus(cpu); > cap = dl_bw_capacity(cpu); > > - if (__dl_overflow(dl_b, cap, old_bw, new_bw)) > + /* > + * Hotplugged CPUs coming online do an enqueue but are not a part of any > + * root domain containing cpu_active() CPUs. So in this case, don't mess > + * with accounting and we can retry later. Later when? It seems a little vague. :) Thanks, Juri