[ 61/86] powerpc/kexec: Disable hard IRQ before kexec

Greg Kroah-Hartman
2013-02-27T00:16:30Z

From: Phileas Fogg <phileas-fogg@mail.ru>

commit 8520e443aa56cc157b015205ea53e7b9fc831291 upstream.

Disable hard IRQ before kexec a new kernel image.
Not doing it can result in corrupted data in the memory segments
reserved for the new kernel.

Signed-off-by: Phileas Fogg <phileas-fogg@mail.ru>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/powerpc/kernel/machine_kexec_64.c | 5 +++++
1 file changed, 5 insertions(+)

--- a/arch/powerpc/kernel/machine_kexec_64.c
+++ b/arch/powerpc/kernel/machine_kexec_64.c
@@ -162,6 +162,8 @@ static int kexec_all_irq_disabled = 0;
static void kexec_smp_down(void *arg)
{
local_irq_disable();
+ hard_irq_disable();
+
mb(); /* make sure our irqs are disabled before we say they are */
get_paca()->kexec_state = KEXEC_STATE_IRQS_OFF;
while(kexec_all_irq_disabled == 0)
@@ -244,6 +246,8 @@ static void kexec_prepare_cpus(void)
wake_offline_cpus();
smp_call_function(kexec_smp_down, NULL, /* wait */0);
local_irq_disable();
+ hard_irq_disable();
+
mb(); /* make sure IRQs are disabled before we say they are */
get_paca()->kexec_state = KEXEC_STATE_IRQS_OFF;

@@ -281,6 +285,7 @@ static void kexec_prepare_cpus(void)
if (ppc_md.kexec_cpu_down)
ppc_md.kexec_cpu_down(0, 0);
local_irq_disable();
+ hard_irq_disable();
}

#endif /* SMP */