Changeset 69703 in vbox

Timestamp:

Nov 15, 2017 12:54:20 PM (7 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

119078

Message:

BIOS: Slightly adjusted boot sector validity test (fixes darwinx86-602.iso).

Location:

trunk/src/VBox/Devices/PC/BIOS

Files:

• boot.c (modified) (2 diffs)
• notes.txt (modified) (1 diff)

trunk/src/VBox/Devices/PC/BIOS/boot.c

@@ -324 +324 @@
     // 0x55AA signature and a valid partition table but zeros in the
     // rest of the boot sector. We do a quick check by comparing the first
-    // two words of boot sector; if identical, the boot sector is
+    // and third word of boot sector; if identical, the boot sector is
     // extremely unlikely to be valid.
     if (bootdrv != 0) bootchk = 0;
@@ -335 +335 @@
 #endif // BX_ELTORITO_BOOT
 
-    if (read_word(bootseg,0) == read_word(bootseg,2)
+    if (read_word(bootseg,0) == read_word(bootseg,4)
       || (bootchk == 0 && read_word(bootseg,0x1fe) != 0xaa55))
     {

trunk/src/VBox/Devices/PC/BIOS/notes.txt

@@ -101 +101 @@
   the top of memory.
 
-
+- Darwin x86 6.0.2 ISO (darwinx86-602.iso) has a bizarre boot sector (using
+  El Torito hard disk emulation) with the first five bytes being zero. It
+  appears to be valid despite the oddity.
 
  286 BIOS