path: root/arch
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authorMarc Zyngier <Marc.Zyngier@arm.com>2013-11-04 16:55:22 +0000
committerAlex Shi <alex.shi@linaro.org>2014-01-14 18:02:28 +0800
commit98eba195f9f6efff2259f17e2261209e47529ab1 (patch)
tree53aeff3e21b07aa8075dc5a037fec200f0145d2b /arch
parent450cdfa9c5713551ab1438ab210679868b52a994 (diff)
arm64: move enabling of GIC before CPUs are set online
Commit 53ae3acd (arm64: Only enable local interrupts after the CPU is marked online) moved the enabling of the GIC after the CPUs are marked online. This has some interesting effect: [...] [<ffffffc0002eefd8>] gic_raise_softirq+0xf8/0x160 [<ffffffc000088f58>] smp_send_reschedule+0x38/0x40 [<ffffffc0000c8728>] resched_task+0x84/0xc0 [<ffffffc0000c8cdc>] check_preempt_curr+0x58/0x98 [<ffffffc0000c8d38>] ttwu_do_wakeup+0x1c/0xf4 [<ffffffc0000c8f90>] ttwu_do_activate.constprop.84+0x64/0x70 [<ffffffc0000cad30>] try_to_wake_up+0x1d4/0x2b4 [<ffffffc0000cae6c>] default_wake_function+0x10/0x18 [<ffffffc0000c5ca4>] __wake_up_common+0x60/0xa0 [<ffffffc0000c7784>] complete+0x48/0x64 [<ffffffc000088bec>] secondary_start_kernel+0xe8/0x110 [...] Here, we end-up calling gic_raise_softirq without having initialized the interrupt controller for this CPU. While this goes unnoticed with GICv2 (the distributor is always accessible), it explodes with GICv3. The fix is to move the call to notify_cpu_starting before we set the secondary CPU online. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch')
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 87340fd5393..35085d66459 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -156,6 +156,11 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
+ * Enable GIC and timers.
+ */
+ notify_cpu_starting(cpu);
+ /*
* OK, now it's safe to let the boot CPU continue. Wait for
* the CPU migration code to notice that the CPU is online
* before we continue.
@@ -163,11 +168,6 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
set_cpu_online(cpu, true);
- /*
- * Enable GIC and timers.
- */
- notify_cpu_starting(cpu);