lapic_suspend/lapic_resume wrong?

From: Juergen Gross
Date: Mon Nov 23 2015 - 02:47:07 EST


Hi,

while trying to find the reason for a hanging kernel during resume
handling I found a strange inconsistency in arch/x86/kernel/apic/apic.c
regarding usage of config options.

Attached patch addresses this, no test done as I'm not sure whether
this is a correct approach. Can you have a look at it, please?


Juergen
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 2f69e3b..bc06c9d 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2270,6 +2270,7 @@ static struct {
unsigned int apic_tmict;
unsigned int apic_tdcr;
unsigned int apic_thmr;
+ unsigned int apic_cmci;
} apic_pm_state;

static int lapic_suspend(void)
@@ -2299,6 +2300,10 @@ static int lapic_suspend(void)
if (maxlvt >= 5)
apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
#endif
+#ifdef CONFIG_X86_MCE_INTEL
+ if (maxlvt >= 6)
+ apic_pm_state.apic_cmci = apic_read(APIC_LVTCMCI);
+#endif

local_irq_save(flags);
disable_local_APIC();
@@ -2355,10 +2360,14 @@ static void lapic_resume(void)
apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
-#if defined(CONFIG_X86_MCE_INTEL)
+#if defined(CONFIG_X86_THERMAL_VECTOR)
if (maxlvt >= 5)
apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
#endif
+#if defined(CONFIG_X86_MCE_INTEL)
+ if (maxlvt >= 6)
+ apic_write(APIC_LVTCMCI, apic_pm_state.apic_cmci);
+#endif
if (maxlvt >= 4)
apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 849500e..524c221 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -39,6 +39,7 @@
#include <asm/irq.h>
#include <asm/idle.h>
#include <asm/io_apic.h>
+#include <asm/i8259.h>
#include <asm/xen/pci.h>
#endif
#include <asm/sync_bitops.h>
@@ -420,7 +421,7 @@ static int __must_check xen_allocate_irq_gsi(unsigned gsi)
return xen_allocate_irq_dynamic();

/* Legacy IRQ descriptors are already allocated by the arch. */
- if (gsi < NR_IRQS_LEGACY)
+ if (gsi < nr_legacy_irqs())
irq = gsi;
else
irq = irq_alloc_desc_at(gsi, -1);
@@ -446,7 +447,7 @@ static void xen_free_irq(unsigned irq)
kfree(info);

/* Legacy IRQ descriptors are managed by the arch. */
- if (irq < NR_IRQS_LEGACY)
+ if (irq < nr_legacy_irqs())
return;

irq_free_desc(irq);