On Tue, Feb 23, 2010 at 09:40:38PM +0100, Manuel Lauss wrote: > > This is a preliminary patch to add a vdso to all user processes. > > Still missing are ELF headers and .eh_frame information. But it is > > enough to allow us to move signal trampolines off of the stack. Note > > that emulation of branch delay slots in the FPU emulator still > > requires the stack. > > > > We allocate a single page (the vdso) and write all possible signal > > trampolines into it. The stack is moved down by one page and the vdso > > is mapped into this space. > > Is there anything special required (i.e. special glibc, ..) to make use of these > fine patches? No - the way the signal handlers return is almost entirely hidden from userland. Only a few applications that have the need to unwind beyond the signal stackframe may run into problems and have to be updated and GDB is one of those that we identified. Ralf
