Richard B. Johnson wrote:
> The target, i.e., the label 'goto' would be the reserved page for the
> system call. The whole purpose was to minimize the number of CPU cycles
> necessary to call 0xfffff000 and return. The system call does not have
> issue a 'far' return, it can do anything it requires. The page at
> 0xfffff000 is mapped into every process and is in that process CS space
> already.
that being the case, why push %cs and reload it without reason as the
code is mapped into every process?
therefore, would it not suffice to use:
...
long_call(); //call to $0xfffff000 via near ret
//code at $0xfffff000 returns directly here when a ret is issued
...
long_call:
pushl $0xfffff000
ret
-
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This archive was generated by hypermail 2b29 : Mon Dec 23 2002 - 22:00:23 EST