powerpc: hard disable irqs in smp_send_stop loop

BugLink: http://bugs.launchpad.net/bugs/1790636
The hard lockup watchdog can fire under local_irq_disable
on platforms with irq soft masking.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
(cherry picked from commit 855bfe0de1a05a01f89975ea8ba9f5521fb0f567)
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Acked-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index c190d6843392a5be65addc2296321935dbf7e95b..7ed7d0c84c0d4156377c9ead097f084979232e2e 100644 (file)
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -570,9 +570,10 @@ static void stop_this_cpu(void *dummy)
        /* Remove this CPU */
        set_cpu_online(smp_processor_id(), false);
 
-       local_irq_disable();
+       hard_irq_disable();
+       spin_begin();
        while (1)
-               ;
+               spin_cpu_relax();
 }
 
 #ifdef CONFIG_NMI_IPI