[src/trunk]: src/sys/arch/alpha/pci Guard against trying to disable an interr...

[mjacob <mjacob%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/b822c5431cff
branches:  trunk
changeset: 481950:b822c5431cff
user:      mjacob <mjacob%NetBSD.org@localhost>
date:      Thu Feb 10 04:31:36 2000 +0000

description:
Guard against trying to disable an interrupt where we'd dereference a
bad pointer.

diffstat:

 sys/arch/alpha/pci/pci_kn300.c |  36 +++++++++++++++++++++++++++++-------
 1 files changed, 29 insertions(+), 7 deletions(-)

diffs (79 lines):

diff -r 35d649e1641a -r b822c5431cff sys/arch/alpha/pci/pci_kn300.c
--- a/sys/arch/alpha/pci/pci_kn300.c    Thu Feb 10 03:06:53 2000 +0000
+++ b/sys/arch/alpha/pci/pci_kn300.c    Thu Feb 10 04:31:36 2000 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: pci_kn300.c,v 1.16 1999/12/15 22:25:21 thorpej Exp $ */
+/* $NetBSD: pci_kn300.c,v 1.17 2000/02/10 04:31:36 mjacob Exp $ */
 
 /*
  * Copyright (c) 1998 by Matthew Jacob
@@ -32,7 +32,7 @@
 
 #include <sys/cdefs.h>                 /* RCS ID & Copyright macro defns */
 
-__KERNEL_RCSID(0, "$NetBSD: pci_kn300.c,v 1.16 1999/12/15 22:25:21 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pci_kn300.c,v 1.17 2000/02/10 04:31:36 mjacob Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -102,7 +102,7 @@
 
                kn300_pci_intr = alpha_shared_intr_alloc(NIRQ);
                for (g = 0; g < NIRQ; g++) {
-                       alpha_shared_intr_set_maxstrays(kn300_pci_intr, g, 25);
+                       alpha_shared_intr_set_maxstrays(kn300_pci_intr, g, 100);
                        savirqs[g] = (char) -1;
                }
                set_iointr(kn300_iointr);
@@ -222,7 +222,6 @@
 dec_kn300_intr_disestablish(ccv, cookie)
        void *ccv, *cookie;
 {
-
        panic("dec_kn300_intr_disestablish not implemented");
 }
 
@@ -282,8 +281,33 @@
        }
 #endif
 
-       if (alpha_shared_intr_dispatch(kn300_pci_intr, irq))
+       if (alpha_shared_intr_dispatch(kn300_pci_intr, irq)) {
+               /*
+                * Any claim of an interrupt at this level is a hint to
+                * reset the stray interrupt count- elsewise a slow leak
+                * over time will cause this level to be shutdown.
+                *
+                * Unfortunately, there's no clean mechanism to do this yet.
+                */
                return;
+       }
+
+       /*
+        * If we haven't finished configuring yet, or there is no mcp
+        * registered for this level yet, just return.
+        */
+       mcp = alpha_shared_intr_get_private(kn300_pci_intr, irq);
+       if (mcp == NULL || mcp->mcpcia_cc == NULL)
+               return;
+
+       /*
+        * We're getting an interrupt for a device we haven't enabled.
+        * We had better not try and use -1 to find the right bit to disable.
+        */
+       if (savirqs[irq] == -1) {
+               printf("kn300_iointr: stray interrupt vector 0x%lx\n", vec);
+               return;
+       }
 
        /*
         * Stray interrupt; disable the IRQ on the appropriate MCPCIA
@@ -292,8 +316,6 @@
        alpha_shared_intr_stray(kn300_pci_intr, irq, "kn300 irq");
        if (ALPHA_SHARED_INTR_DISABLE(kn300_pci_intr, irq) == 0)
                return;
-
-       mcp = alpha_shared_intr_get_private(kn300_pci_intr, irq);
        kn300_disable_intr(mcp->mcpcia_cc, savirqs[irq]);
 }