Thank you all who replied! 2011/10/2 Ted Unangst <[email protected]>: > On Fri, Sep 30, 2011, Vadim Zhukov wrote: >> Hello all. >> >> After some talks on opennet.ru I dived into the sys/uvm/ and other >> places, having a few more or less tech-nical questions raised now. Can >> anybody answer them? > > Very nice. > >> 1. amap_share_protect() in sys/uvm/uvm_amap.c is totally unused, is there >> any point for keeping it around? > > No, there's probably more than a few functions no longer used. B It's > hard to know when you delete the last call to a function. B Diffs welcome.
OK, I'll try to automate this process. :) >> 2. Am I right that W^X techniques like segment splitting on i386 are not >> used in kernel? > > Not presently. > >> 2a. If yes, what's the main stopper here? > > A diff. > >> 3. What's the point in keeping sys/arch/i386/i386/pmapae.c? Are there any >> plans for re-enabling PAE support? > > Someday, if somebody gets it to work, it'd be nice to have. B Some people > may want to keep running i386, but most new CPUs let you use the NX bit > with PAE, so it's helpful even with small amounts of memory. > >> 4. Stack gap limit (STACKGAP_RANDOM) on almost all archs is 256*1024 >> (some use less). Are there any pitfalls in growing it on (64-bit) archs >> like amd64, changing random bit count from 15 to something more >> effective? > > I can't think of any reason why 1GB or even more wouldn't work on amd64. > You can try it and see. I'm a bad guy - running i386 only now. :( Thanks again! -- WBR, Vadim Zhukov
