powerpc: Fix a lazy irq related WARING in arch_local_irq_restore()
The pseries CPU hotplug code uses cede_processor without properly
synchronizing the SW and HW interrupt enable state. This fixes
it using the same helpers that were written for the idle code.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
=======================
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/platforms/pseries/plpar_wrappers.h b/arch/powerpc/platforms/pseries/plpar_wrappers.h
index e6cc34a..b933849 100644
--- a/arch/powerpc/platforms/pseries/plpar_wrappers.h
+++ b/arch/powerpc/platforms/pseries/plpar_wrappers.h
@@ -2,6 +2,7 @@
#define _PSERIES_PLPAR_WRAPPERS_H
#include <linux/string.h>
+#include <linux/irqflags.h>
#include <asm/hvcall.h>
#include <asm/paca.h>
@@ -41,7 +42,14 @@
u8 old_latency_hint = get_cede_latency_hint();
set_cede_latency_hint(latency_hint);
+
rc = cede_processor();
+#ifdef CONFIG_TRACE_IRQFLAGS
+ /* Ensure that H_CEDE returns with IRQs on */
+ if (WARN_ON(!(mfmsr() & MSR_EE)))
+ __hard_irq_enable();
+#endif
+
set_cede_latency_hint(old_latency_hint);
return rc;