1 files changed, 15 insertions, 0 deletions

diff --git a/arch/alpha/kernel/sys_rawhide.c b/arch/alpha/kernel/sys_rawhide.c
index 581d08c70b92..672cb2df53df 100644
--- a/arch/alpha/kernel/sys_rawhide.c
+++ b/arch/alpha/kernel/sys_rawhide.c
@@ -52,6 +52,9 @@ rawhide_update_irq_hw(int hose, int mask)
         *(vuip)MCPCIA_INT_MASK0(MCPCIA_HOSE2MID(hose));
 }
 
+#define hose_exists(h) \
+  (((h) < MCPCIA_MAX_HOSES) && (cached_irq_masks[(h)] != 0))
+
 static inline void 
 rawhide_enable_irq(unsigned int irq)
 {
@@ -59,6 +62,9 @@ rawhide_enable_irq(unsigned int irq)
 
         irq -= 16;
         hose = irq / 24;
+        if (!hose_exists(hose)) /* if hose non-existent, exit */
+                return;
+
         irq -= hose * 24;
         mask = 1 << irq;
 
@@ -76,6 +82,9 @@ rawhide_disable_irq(unsigned int irq)
 
         irq -= 16;
         hose = irq / 24;
+        if (!hose_exists(hose)) /* if hose non-existent, exit */
+                return;
+
         irq -= hose * 24;
         mask = ~(1 << irq) | hose_irq_masks[hose];
 
@@ -93,6 +102,9 @@ rawhide_mask_and_ack_irq(unsigned int irq)
 
         irq -= 16;
         hose = irq / 24;
+        if (!hose_exists(hose)) /* if hose non-existent, exit */
+                return;
+
         irq -= hose * 24;
         mask1 = 1 << irq;
         mask = ~mask1 | hose_irq_masks[hose];
@@ -169,6 +181,9 @@ rawhide_init_irq(void)
 
         mcpcia_init_hoses();
 
+        /* Clear them all; only hoses that exist will be non-zero. */
+        for (i = 0; i < MCPCIA_MAX_HOSES; i++) cached_irq_masks[i] = 0;
+
         for (hose = hose_head; hose; hose = hose->next) {
                 unsigned int h = hose->index;
                 unsigned int mask = hose_irq_masks[h];