On Nov 13, 2007 3:37 PM, Kevin D. Kissell <kevink@xxxxxxxx> wrote: > Franck a dit: > > > Another reason is to get rid of the classic trampoline the kernel installs > > > on the stack. On some multiprocessor systems it requires a cacheflush > > > operation to be performed on all processors which is expensive. Having > > > the trampoline in a vDSO would solve that. > > > > > > > And the stack wouldn't need to have exec permission anymore. > > True, though it should perhaps be noted that currently it's only on 4KSc/Sd > systems (which I know you work on) where it's even possible for the stack > *not* to have exec permissions, since the classical MIPS MMU gives > execute permission to any page that is readable. > Well, the noexec stack is pretty usefull I think. I can't believe it will be limited to these 2 systems in the near future... -- Franck