Re: Non-executable mappings now in NetBSD too

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Date: Sat, 30 Aug 2003 20:50:45 -0600
To: <hackers@freebsd.org>

> Whilst the Java bytecode is not natively executable, a JIT JVM >needs to be able towrite and immediately execute native code. >The OpenBSD W^X approach would require system calls between the >compilation and execution steps. My understanding of current JIT >is that the compilation is done is very small pieces and adding >the overhead of a pair of system calls would basically kill it.

Even simpler to compile to a temporary file and then exit the temporary file. Woohoo, potential race condition! <br><br>
...Or you could make a nifty new system call that creates a pipe to a newly forked child process. You write the compiled executable to the fork, and the child jumps to the begining of that compiled code as soon as your parent process closes the pipe!<br><br>
Gratuitous/pointless, but fun to think about.

Andrew Lankford

 
                   
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• Previous message: Sandeep Kumar Davu: "HOW TO RETREIVE DATA FROM KERNEL."
• Maybe in reply to: Pedro F. Giffuni: "Non-executable mappings now in NetBSD too"
• Next in thread: Pedro F. Giffuni: "Re: Non-executable mappings now in NetBSD too"
• Reply: Pedro F. Giffuni: "Re: Non-executable mappings now in NetBSD too"
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