lkml.org 
[lkml]   [2013]   [Jul]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/5] metag: smp: enable irqs after set_cpu_online
Date
In secondary_start_kernel() interrupts should be enabled with
local_irq_enable() after the cpu is marked as online with
set_cpu_online(). Otherwise it's possible for a timer interrupt to
trigger a softirq, which if the cpu is marked as offline may have it's
affinity altered.

Reported-by: Kirill Tkhai <tkhai@yandex.ru>
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
---
arch/metag/kernel/smp.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/arch/metag/kernel/smp.c b/arch/metag/kernel/smp.c
index b813515..09979f2 100644
--- a/arch/metag/kernel/smp.c
+++ b/arch/metag/kernel/smp.c
@@ -379,12 +379,7 @@ asmlinkage void secondary_start_kernel(void)

setup_priv();

- /*
- * Enable local interrupts.
- */
- tbi_startup_interrupt(TBID_SIGNUM_TRT);
notify_cpu_starting(cpu);
- local_irq_enable();

pr_info("CPU%u (thread %u): Booted secondary processor\n",
cpu, cpu_2_hwthread_id[cpu]);
@@ -398,6 +393,12 @@ asmlinkage void secondary_start_kernel(void)
set_cpu_online(cpu, true);

/*
+ * Enable local interrupts.
+ */
+ tbi_startup_interrupt(TBID_SIGNUM_TRT);
+ local_irq_enable();
+
+ /*
* OK, it's off to the idle thread for us
*/
cpu_startup_entry(CPUHP_ONLINE);
--
1.8.1.2



\
 
 \ /
  Last update: 2013-07-01 18:41    [W:0.179 / U:1.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site