[IA64] SGI Altix : fix a force_interrupt bug on altix

If the interrupt has been disabled, don't call the force_interrupt provider.
Doing so can result in an infinite runaway interrupt loop.

Signed-off-by: Mike Habeck <habeck@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/arch/ia64/sn/kernel/irq.c b/arch/ia64/sn/kernel/irq.c
index bfa43e4c7ef7..360047389449 100644
--- a/arch/ia64/sn/kernel/irq.c
+++ b/arch/ia64/sn/kernel/irq.c
@@ -405,7 +405,10 @@ sn_call_force_intr_provider(struct sn_irq_info *sn_irq_info)
         struct sn_pcibus_provider *pci_provider;
 
         pci_provider = sn_pci_provider[sn_irq_info->irq_bridge_type];
-        if (pci_provider && pci_provider->force_interrupt)
+
+        /* Don't force an interrupt if the irq has been disabled */
+        if (!(irq_desc[sn_irq_info->irq_irq].status & IRQ_DISABLED) &&
+            pci_provider && pci_provider->force_interrupt)
                 (*pci_provider->force_interrupt)(sn_irq_info);
 }