[PATCH 1/2] x86: initialize stack canary in secondary start

From: Jacob Pan
Date: Thu Sep 17 2009 - 10:36:43 EST


some secondary clockevent setup code needs to call request_irq, which will
cause fake stack check failure in schedule() if voluntary preemption
model is chosen, it is safe to have stack canary initialized here early,
since start_secondary() does not return.

Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxx>
---
arch/x86/kernel/smpboot.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 678d0b8..56ce974 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -48,6 +48,7 @@
#include <linux/err.h>
#include <linux/nmi.h>
#include <linux/tboot.h>
+#include <linux/stackprotector.h>

#include <asm/acpi.h>
#include <asm/desc.h>
@@ -324,6 +325,9 @@ notrace static void __cpuinit start_secondary(void *unused)
/* enable local interrupts */
local_irq_enable();

+ /* to prevent fake stack check failure in clock setup */
+ boot_init_stack_canary();
+
x86_cpuinit.setup_percpu_clockev();

wmb();
--
1.6.5.3

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