On Fri, May 30, 2014 at 1:20 PM, H. Peter Anvin <hpa@xxxxxxxxx> wrote: > On 05/30/2014 01:11 PM, Andy Lutomirski wrote: >> On Fri, May 30, 2014 at 1:05 PM, H. Peter Anvin <hpa@xxxxxxxxx> wrote: >>> On 05/30/2014 01:00 PM, Andy Lutomirski wrote: >>>> >>>> Do the flags go in the ELF loader or in the executable we're running? >>>> Or both (and, if both, do we and them or or them)? >>>> >>>> I think the interpreter makes a little more sense in general: for the >>>> most part, use of vsyscalls is a property of the runtime environment, >>>> not of the program being run. But maybe this is naive. >>>> >>> >>> They go into each object which becomes part of the running program, i.e. >>> executable, dynamic libraries, and dynamic linker. >> >> Well, sure, but the kernel is not about to start reading ELF headers >> in dynamic libraries. So we need to make a decision based on the >> interpreter and the executable. The conservative approach is to >> require both to have the flag set *and* to offer a prctl to twiddle >> the flags. Then userspace loaders can do whatever they want, and >> distros get to rebuild the world :) >> > > Yes, something like that. I'll hack something up once the merge window closes. Or maybe sooner if you commit my vsyscall patches from a few days ago. Otherwise I'm just going to confuse my git tree too much :) --Andy > > -hpa > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-api" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Andy Lutomirski AMA Capital Management, LLC -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
