On Tue, 2011-08-02 at 01:45 +0400, Dmitry V. Levin wrote: > On Sat, Jun 25, 2011 at 11:34:23AM +0200, Denys Vlasenko wrote: > > This is a big change. I am not entirely sure it is correct, > > so this patch is meant more like a RFC rather than a proposal > > to apply it right away. > > I've read your series of patches several times and tested it with several > kernel versions. It looks correct. > > > Current code plays some ungodly tricks, trying to not detach > > thread group leader until all threads exit. > > > > Also, it detaches from a tracee when signal delivery is detected > > which will cause tracee to exit. > [...] > > I need to look in the past to figure out why we even do it. > > First guess is that it's a workaround for old kernel bugs. > > How old those buggy kernels might be?
We might have moderately bad news. I tested current git on 2.4.32 kernel (ISO image from http://mirrors.kernel.org/openwall/Owl/2.0-release/iso/Owl-2.0-release-i386.iso.gz ) and test/childthread.c testcase apparently shows that exit_group syscall *returns* under ptrace. IOW: the "detach before exit" might be a necessity even on latest 2.4 kernels. Need to test 2.4.37... -- vda ------------------------------------------------------------------------------ Get a FREE DOWNLOAD! and learn more about uberSVN rich system, user administration capabilities and model configuration. Take the hassle out of deploying and managing Subversion and the tools developers use with it. http://p.sf.net/sfu/wandisco-d2d-2 _______________________________________________ Strace-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/strace-devel
