[src/trunk]: src/usr.sbin/sysinst/arch/mac68k Disable the code that tries to ...

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

details:   https://anonhg.NetBSD.org/src/rev/9beaca2accd5
branches:  trunk
changeset: 345508:9beaca2accd5
user:      dholland <dholland%NetBSD.org@localhost>
date:      Tue May 31 02:49:50 2016 +0000

description:
Disable the code that tries to prepare a new partition table (but doesn't
do anything with it...) because it's zooming off the end of the array it's
trying to use.

It looks to me as if NEW_MAP_SIZE has been accidentally used as both
the number of blocks occupied by the new partition table and also the
number of entries in it. Or something. This needs platform knowledge
to sort out. XXX.

Workaround for PR 50757.

diffstat:

 usr.sbin/sysinst/arch/mac68k/md.c |  18 +++++++++++++++++-
 1 files changed, 17 insertions(+), 1 deletions(-)

diffs (39 lines):

diff -r d82338a285f7 -r 9beaca2accd5 usr.sbin/sysinst/arch/mac68k/md.c
--- a/usr.sbin/sysinst/arch/mac68k/md.c Tue May 31 02:37:15 2016 +0000
+++ b/usr.sbin/sysinst/arch/mac68k/md.c Tue May 31 02:49:50 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: md.c,v 1.4 2015/05/11 12:57:55 martin Exp $ */
+/*     $NetBSD: md.c,v 1.5 2016/05/31 02:49:50 dholland Exp $ */
 
 /*
  * Copyright 1997 Piermont Information Systems Inc.
@@ -173,6 +173,21 @@
         *  need to completely initialize the disk.
         */
        pm->dlsize = disklabel.d_secperunit;
+/*
+ * XXX this code is broken: it accesses off the end of new_map[],
+ * because NEW_MAP_SIZE is substantially larger than the number of
+ * entries in new_map[]. Based on the description of struct
+ * apple_part_map_entry in sys/bootblock.h, and the usage of it in
+ * new_map[], NEW_MAP_SIZE is expected to be a block count, not an
+ * entry count. As far I can tell the logic here is just wrong; it
+ * needs someone with platform knowledge to sort it out.
+ *
+ * Note that nothing uses the data this writes into new_map[] so
+ * disabling it should have no adverse consequences.
+ *
+ *   - dholland 20160530
+ */
+#if 0 /* XXX broken */
        for (i=0;i<NEW_MAP_SIZE;i++) {
           if (i > 0)
                new_map[i].pmPyPartStart = new_map[i-1].pmPyPartStart +
@@ -185,6 +200,7 @@
           }
           pm->dlsize -= new_map[i].pmPartBlkCnt;
        }
+#endif /* 0 - broken */
        pm->dlsize = disklabel.d_secperunit;
 #if 0
        msg_display(MSG_dldebug, blk_size, pm->dlcyl, pm->dlhead, pm->dlsec, pm->dlsize);