diff options
author | Li Zhong <zhong@linux.vnet.ibm.com> | 2012-10-17 21:30:13 +0000 |
---|---|---|
committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2013-01-10 14:43:45 +1100 |
commit | fb9125680d0e7c23eae7c6000acc91ea26acab9c (patch) | |
tree | 4f961ee02e1661876e6c2e565c8085558a0e9281 | |
parent | 323a6bf1d6f4ec7907d9d8aacb4ae9590f755dda (diff) |
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>
-rw-r--r-- | arch/powerpc/platforms/pseries/hotplug-cpu.c | 8 | ||||
-rw-r--r-- | arch/powerpc/platforms/pseries/plpar_wrappers.h | 8 |
2 files changed, 16 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c index a38956269fbf..217ca5c75b20 100644 --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c @@ -127,9 +127,16 @@ static void pseries_mach_cpu_die(void) get_lppaca()->donate_dedicated_cpu = 1; while (get_preferred_offline_state(cpu) == CPU_STATE_INACTIVE) { + while (!prep_irq_for_idle()) { + local_irq_enable(); + local_irq_disable(); + } + extended_cede_processor(cede_latency_hint); } + local_irq_disable(); + if (!get_lppaca()->shared_proc) get_lppaca()->donate_dedicated_cpu = 0; get_lppaca()->idle = 0; @@ -137,6 +144,7 @@ static void pseries_mach_cpu_die(void) if (get_preferred_offline_state(cpu) == CPU_STATE_ONLINE) { unregister_slb_shadow(hwcpu); + hard_irq_disable(); /* * Call to start_secondary_resume() will not return. * Kernel stack will be reset and start_secondary() diff --git a/arch/powerpc/platforms/pseries/plpar_wrappers.h b/arch/powerpc/platforms/pseries/plpar_wrappers.h index e6cc34a67053..b93384929c4c 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 @@ static inline long extended_cede_processor(unsigned long latency_hint) 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; |