[] FreeBSD bug: kern/86767 bogus "slice starts beyond end of the disk:..." 
   mount.
[] Most accesses to USB floppy drives, especially mounts, tend to result
   in bogus "slice starts beyond end of the disk:..." errors.
  [] if the boot parameter block claims the device is a floppy media
     then it is NOW assumed there is no partition table to check.
  [] Much thanks to Bruce Evans <bde@zeta.org.au> for hints on where to 
     drop this patch.

--- sys/msdosfs/bootsect.h	Fri Aug 27 20:48:06 1999
+++ sys/msdosfs/bootsect.h	Mon Oct  3 18:04:27 2005
@@ -94,6 +94,34 @@
 	struct bootsector710 bs710;
 };
 
+
+  /* selected media description bytes within bsPBP. used to detect 
+   * media that only has one slice on it. for now this is expected 
+   * to be floppy media.
+				  ghealton@exit109.com  &  ... @lumeta.com */
+	/* (as of 2005-09 floppy media description bytes were available at
+	    http://support.microsoft.com/default.aspx?scid=kb;en-us;140418
+	    http://www.win.tue.nl/~aeb/linux/fs/fat/fat-1.html)
+                                      /* size DOS  Capicty sides  tks  spt */
+#define MSDOS_MEDIA_ONESLICE0  0xF9   /* 5.25 3.0 1200KB     2     80  15  */
+#define MSDOS_MEDIA_ONESLICE1  0xFF   /* 5.25 1.1  320KB     2     40   8  */
+
+#define MSDOS_MEDIA_ONESLICE2  0xF0   /* 3.5  ?.? 2880KB     2     80  36  */
+
+#define MSDOS_MEDIA_oneslice(c) ( \
+	    ( md >= MSDOS_MEDIA_ONESLICE0 && md <= MSDOS_MEDIA_ONESLICE1 ) \
+	 || ( md == MSDOS_MEDIA_ONESLICE2 ) \
+			        )
+		/* if floppies with slice tables are ever used I suspose
+		   that a check for s1-s4 could be made to verify the
+		   first byte of each slice table is 0x00 or 0x80 AND
+		   at most one byte has the 0x80 value in it AND the
+		   remaining bytes of each slice table are not all zeros. If
+		   this test is met you might be able to assume a slice
+		   table exists. But I would make such a compile-option for
+		   those expressly asking for it. */
+
+
 #if 0
 /*
  * Shorthand for fields in the bpb.
--- sys/kern/subr_diskmbr.c	Fri Jan 28 05:22:07 2000
+++ sys/kern/subr_diskmbr.c	Mon Oct  3 18:16:19 2005
@@ -42,6 +42,7 @@
 #include <sys/systm.h>
 #include <sys/buf.h>
 #include <sys/conf.h>
+#include <msdosfs/bootsect.h>	  /* BOOTSIG0, BOOTSIG1, MSDOS_MEDIA_oneslice */
 #ifdef PC98
 #define	PC98_ATCOMPAT
 #define	dsinit			atcompat_dsinit
@@ -200,13 +201,26 @@
 	/* Weakly verify it. */
 	cp = bp->b_data;
 	sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, RAW_PART, partname);
-	if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) {
+	if (cp[0x1FE] != BOOTSIG0 || cp[0x1FF] != BOOTSIG1) {
 		if (bootverbose)
 			printf("%s: invalid primary partition table: no magic\n",
 			       sname);
 		error = EINVAL;
 		goto done;
 	}
+
+      {		/* ghealton@exit109.com   also ....@lumeta.com */
+       /* check if media description byte within range of known floppy medias */
+
+	u_char  md = cp[0x15];		/* set local easy access variable */
+
+	if ( MSDOS_MEDIA_oneslice(md) ) { 
+		/* this media only uses a single slice (e.g., floppies)  */
+
+		error = 0;
+		goto done;	/* no partition table to process */
+	}
+      }
 
 	/* Make a copy of the partition table to avoid alignment problems. */
 	memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy));