xen/events: Always allocate legacy interrupts on PV guests
After commit 8c058b0b9c34 ("x86/irq: Probe for PIC presence before
allocating descs for legacy IRQs") early_irq_init() will no longer
preallocate descriptors for legacy interrupts if PIC does not
exist, which is the case for Xen PV guests.
Therefore we may need to allocate those descriptors ourselves.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
diff --git a/arch/arm/include/asm/irq.h b/arch/arm/include/asm/irq.h
index be1d07d..1bd9510de 100644
--- a/arch/arm/include/asm/irq.h
+++ b/arch/arm/include/asm/irq.h
@@ -40,6 +40,11 @@
#define arch_trigger_all_cpu_backtrace(x) arch_trigger_all_cpu_backtrace(x)
#endif
+static inline int nr_legacy_irqs(void)
+{
+ return NR_IRQS_LEGACY;
+}
+
#endif
#endif
diff --git a/arch/arm64/include/asm/irq.h b/arch/arm64/include/asm/irq.h
index bbb251b..8b9bf54 100644
--- a/arch/arm64/include/asm/irq.h
+++ b/arch/arm64/include/asm/irq.h
@@ -21,4 +21,9 @@
}
#define acpi_irq_init acpi_irq_init
+static inline int nr_legacy_irqs(void)
+{
+ return 0;
+}
+
#endif
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 @@
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 @@
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);