From bd9f943e5d2a42d864f9692477a25034c9d47dcc Mon Sep 17 00:00:00 2001 From: Pavel Tatashin Date: Mon, 30 Jul 2018 09:52:52 -0400 Subject: [PATCH] sched/clock: Disable interrupts when calling generic_sched_clock_init() sched_clock_init() used be called early during boot when interrupts were still disabled. After the recent changes to utilize sched clock early the sched_clock_init() call happens when interrupts are already enabled, which triggers the following warning: WARNING: CPU: 0 PID: 0 at kernel/time/sched_clock.c:180 sched_clock_register+0x44/0x278 [] (warn_slowpath_null) from [] (sched_clock_register+0x44/0x278) [] (sched_clock_register) from [] (generic_sched_clock_init+0x28/0x88) [] (generic_sched_clock_init) from [] (sched_clock_init+0x54/0x74) [] (sched_clock_init) from [] (start_kernel+0x310/0x3e4) [] (start_kernel) from [<00000000>] ( (null)) Disable IRQs for the duration of generic_sched_clock_init(). Fixes: 857baa87b642 ("sched/clock: Enable sched clock early") Signed-off-by: Pavel Tatashin Reported-by: Guenter Roeck Signed-off-by: Thomas Gleixner Cc: Peter Zijlstra Cc: steven.sistare@oracle.com Cc: daniel.m.jordan@oracle.com Link: https://lkml.kernel.org/r/20180730135252.24599-1-pasha.tatashin@oracle.com --- kernel/sched/clock.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c index 811a39aca1ce..e3e3b979f9bd 100644 --- a/kernel/sched/clock.c +++ b/kernel/sched/clock.c @@ -452,7 +452,9 @@ EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event); void __init sched_clock_init(void) { static_branch_inc(&sched_clock_running); + local_irq_disable(); generic_sched_clock_init(); + local_irq_enable(); } u64 sched_clock_cpu(int cpu)