From owner-freebsd-hackers  Fri Apr  6  9:38:41 2001
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From: Doug Ambrisko <ambrisko@ambrisko.com>
Message-Id: <200104061638.f36GcbP27846@ambrisko.com>
Subject: Fix for CDROM boot for IBM PC desktops
To: freebsd-hackers@freebsd.org
Date: Fri, 6 Apr 2001 09:38:37 -0700 (PDT)
Cc: dhw@whistle.com, mark@whistle.com
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On on IBM PC desktops a FreeBSD bootable CDROM won't boot and it hangs.  
This has been reported in several places.

The problem is that some BIOSes namely IBM's writes to the boot sector
of the floppy to potentially update the parameters for the emulated
floppy used for the El Torrito boot.  Since we do not allocate space
for a typical MSDOS "Boot Sector" when the BIOS updates this area
it then ends up modifying the boot code which is not a good thing.
The boot code then fails in random ways.  I also did a work-around
for linking the address of "xread" into boot2.c.

The fix is in PR i386/26382:
	http://www.freebsd.org/cgi/query-pr.cgi?pr=26382
This would be great to get into 4.3 but probably won't make it.

Thanks, 

Doug A.

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