[src/trunk]: src/sys/kern Make m_copydata panics more verbose

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

details:   https://anonhg.NetBSD.org/src/rev/95919ddb7bae
branches:  trunk
changeset: 787671:95919ddb7bae
user:      matt <matt%NetBSD.org@localhost>
date:      Fri Jun 28 01:23:05 2013 +0000

description:
Make m_copydata panics more verbose

diffstat:

 sys/kern/uipc_mbuf.c |  16 ++++++++++++----
 1 files changed, 12 insertions(+), 4 deletions(-)

diffs (49 lines):

diff -r d3927996d381 -r 95919ddb7bae sys/kern/uipc_mbuf.c
--- a/sys/kern/uipc_mbuf.c      Fri Jun 28 01:21:45 2013 +0000
+++ b/sys/kern/uipc_mbuf.c      Fri Jun 28 01:23:05 2013 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: uipc_mbuf.c,v 1.150 2013/06/27 17:47:18 christos Exp $ */
+/*     $NetBSD: uipc_mbuf.c,v 1.151 2013/06/28 01:23:05 matt Exp $     */
 
 /*-
  * Copyright (c) 1999, 2001 The NetBSD Foundation, Inc.
@@ -62,7 +62,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: uipc_mbuf.c,v 1.150 2013/06/27 17:47:18 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: uipc_mbuf.c,v 1.151 2013/06/28 01:23:05 matt Exp $");
 
 #include "opt_mbuftrace.h"
 #include "opt_nmbclusters.h"
@@ -865,12 +865,17 @@
 {
        unsigned        count;
        void *          cp = vp;
+       struct mbuf     *m0 = m;
+       int             len0 = len;
+       int             off0 = off;
+       void            *vp0 = vp;
 
        if (off < 0 || len < 0)
                panic("m_copydata: off %d, len %d", off, len);
        while (off > 0) {
                if (m == NULL)
-                       panic("m_copydata: m == NULL, off %d", off);
+                       panic("m_copydata(%p,%d,%d,%p): m=NULL, off=%d (%d)",
+                           m0, len0, off0, vp0, off, off0 - off);
                if (off < m->m_len)
                        break;
                off -= m->m_len;
@@ -878,7 +883,10 @@
        }
        while (len > 0) {
                if (m == NULL)
-                       panic("m_copydata: m == NULL, len %d", len);
+                       panic("m_copydata(%p,%d,%d,%p): "
+                           "m=NULL, off=%d (%d), len=%d (%d)",
+                           m0, len0, off0, vp0,
+                           off, off0 - off, len, len0 - len);
                count = min(m->m_len - off, len);
                memcpy(cp, mtod(m, char *) + off, count);
                len -= count;