Date: Wed, 16 Jul 1997 15:45:25 -0700 From: Wayne Scott <wscott@ichips.intel.com> To: Terry Lambert <terry@lambert.org> Cc: smp@csn.net (Steve Passe), smp@FreeBSD.ORG, current@FreeBSD.ORG Subject: Re: self modifying kernel code Message-ID: <199707162245.PAA07524@pdxlx008.intel.com> In-Reply-To: Your message of "Wed, 16 Jul 1997 14:41:26 PDT." <199707162141.OAA01599@phaeton.artisoft.com>
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> Are we assuming that the processors will be Pentium only? The icache
> is not written back prior to the P5. This takes a significant number
> of NOP's to flush the pipeline (as discussed in Van Guilluwe's "The
> Undocumented PC" in the section where he investigates instruction cache
> depth using self-modifying code).
At startup the call is to a routine that computes the correct target
address. In the fixup routine you change the call address and then
jump to the target directly. It will be a long time before you
actually execute the modified code.
-Wayne
Wayne Scott MD6 Architecture
wscott@ichips.intel.com Work #: (503) 264-4165
Disclaimer: All views expressed are my own opinions, and not necessarily
those of Intel Corporation.
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