lkml.org 
[lkml]   [2020]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v1 2/3] arm: disable irq on cpu shutdown flow
Date
Disable irq on cpu shutdown flow to ensure interrupts
did not bother this cpu after status as offline.

To avoid suspicious RCU usage
[0:swapper/0]RCU used illegally from offline CPU! ...
[0:swapper/0]lockdep: [name:lockdep&]cpu_id = 0, cpu_is_offline = 1

Signed-off-by: Hanks Chen <hanks.chen@mediatek.com>
---
arch/arm/kernel/smp.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 48099c6e1e4a..6b8f72490320 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -262,6 +262,12 @@ int __cpu_disable(void)
remove_cpu_topology(cpu);
#endif

+ /*
+ * we disable irq here to ensure interrupts
+ * did not bother this cpu after status as offline.
+ */
+ local_irq_disable();
+
/*
* Take this CPU offline. Once we clear this, we can't return,
* and we must not schedule until we're ready to give up the cpu.
@@ -600,11 +606,11 @@ static void ipi_cpu_stop(unsigned int cpu)
raw_spin_unlock(&stop_lock);
}

- set_cpu_online(cpu, false);
-
local_fiq_disable();
local_irq_disable();

+ set_cpu_online(cpu, false);
+
while (1) {
cpu_relax();
wfe();
--
2.18.0
\
 
 \ /
  Last update: 2020-11-27 15:17    [W:0.080 / U:2.220 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site