Commit 1b537c7d1e58 ("sched/core: Remove check of p->sched_class") placed
"current->sched_class = &fair_sched_class" before call of init_idle() which
immediately set sched_class back to idle_sched_class.
This patch reverts this piece because after commit de9b8f5dcbd9 ("sched:
Fix crash trying to dequeue/enqueue the idle thread") init_idle() doesn't
call do_set_cpus_allowed() and nobody will dereference ->sched_class.
[ Probably this pretending is no longer required and could be removed,
or maybe it helps in catching bugs like sleeping during early bootup? ]
Signed-off-by: Konstantin Khlebnikov <[email protected]>
Fixes: 1b537c7d1e58 ("sched/core: Remove check of p->sched_class")
Cc: Yao Dongdong <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Sasha Levin <[email protected]>
---
kernel/sched/core.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 51d7105f529a..c23aee77d10d 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7481,11 +7481,6 @@ void __init sched_init(void)
enter_lazy_tlb(&init_mm, current);
/*
- * During early bootup we pretend to be a normal task:
- */
- current->sched_class = &fair_sched_class;
-
- /*
* Make us the idle thread. Technically, schedule() should not be
* called from this thread, however somewhere below it might be,
* but because we are the idle thread, we just pick up running again
@@ -7495,6 +7490,11 @@ void __init sched_init(void)
calc_load_update = jiffies + LOAD_FREQ;
+ /*
+ * During early bootup we pretend to be a normal task:
+ */
+ current->sched_class = &fair_sched_class;
+
#ifdef CONFIG_SMP
zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT);
/* May be allocated at isolcpus cmdline parse time */
