On Oct 13, 2011, at 12:09 PM, Kostik Belousov wrote: > On Thu, Oct 13, 2011 at 11:30:12AM -0700, Marcel Moolenaar wrote: >> >> On Oct 13, 2011, at 11:20 AM, Kostik Belousov wrote: >> >>> The two commits removed NX support for .data/.bss for 32bit binaries >>> Thon amd64. is is too unfortunate. Can we claim that only old >>> Thbinaries need this hack ? >> >> I don't know. When did our ABI for i386 change to have NX by default? > I think it changed de-facto when NX appears to be supported by hardware. > In other words, PF_R->PF_X was always considered a coincident, and not > a promise.
That's really besides the point. ABI changes are made deliberately and ABIs must be well-documented for anyone to adhere to it. You can't post hoc wave your hand and say that at some unspecified time in the past the ABI changed: at what precise time does "supported by hardware mean" and how does that tie to a major FreeBSD version? Point in case: the JDK 1.4.x still works on FreeBSD 9.x (i386), so the ABI really hasn't changed at all in that respect. > I think we can claim that the moment FreeBSD gained PAE support, it happen. We cannot make that claim at at. > I would suggest to add a sysctl, say kern.elf32.readable_nx, with > the values: > 0 - strictly follow segment permissions > 1 - PF_R implies PF_X if p_osrel < 600000 > 2 - PF_R always implied PF_X > for 32bit binaries. A sysctl is a good idea, but I would just give it a 0/1 value. Adding a "p_osrel < 600000" case is entirely without grounds. -- Marcel Moolenaar mar...@xcllnt.net _______________________________________________ svn-src-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
