From owner-cvs-all  Wed Mar 21 12: 9:25 2001
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From: John Baldwin <jhb@FreeBSD.org>
Date: Wed, 21 Mar 2001 12:08:08 -0800 (PST)
To: cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org
Subject: cvs commit: src/sys/boot/i386/btx/btx btx.s
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jhb         2001/03/21 12:08:08 PST

  Modified files:
    sys/boot/i386/btx/btx btx.s 
  Log:
  Always disable paging when exiting back to real mode after receiving a
  fatal trap.  Also, reload the GDT register to point to BTX's GDT before
  playing around with the segment registers to return to real mode.  This is
  helpful if the kernel causes a fatal exception before it has setup its own
  IDT and fault handlers.  For example, if one happens to break mtx_init().
  Without these changes BTX would recursively page fault (if paging was not
  disabled) or triple fault and reset the CPU (without the GDT reload)
  instead of providing a potentially useful register dump.
  
  Reviewed by:	rnordier
  
  Revision  Changes    Path
  1.24      +5 -5      src/sys/boot/i386/btx/btx/btx.s


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