On 05/18, Ingo Molnar wrote: > > * Oleg Nesterov <oleg@xxxxxxxxxx> wrote: > > > On 05/17, Ingo Molnar wrote: > > > > > > > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=13107 > > > > Subject : LTP 20080131 causes defunct processes w/2.6.30-rc1 > > > > Submitter : Kumar Gala <galak@xxxxxxxxxxxxxxxxxxx> > > > > Date : 2009-04-09 15:43 (38 days old) > > > > First-Bad-Commit: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=b3bfa0cba867f23365b81658b47efd906830879b > > > > References : http://marc.info/?l=linux-kernel&m=123929187208953&w=4 > > > > http://lkml.org/lkml/2009/4/10/193 > > > > Handled-By : Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx> > > > > > > Oleg says in that thread that it's as-designed, and followup > > > questions were not replied to (yet). > > > > Yes, I think this is false alarm. Perhaps I missed something, and > > I am waiting for more info from Kumar, but it looks like ltp was > > already changed to skip the "{ PTRACE_ATTACH, 1, EPERM }" test on > > kernels after 2.6.25 > > Btw., why did the patch (and the revert) make any difference to the > test? Timing differences look improbable. Because before this series /sbin/init always ignored SIGSTOP. Now, ptracer does PTRACE_ATTACH and exits without clearing the pending SIGSTOP. init dequeues this signal and becomes TASK_STOPPED. Consider: $ sleep 1000 & [1] 875 $ grep State: /proc/`pidof sleep`/status State: S (sleeping) $ perl -e 'syscall 101, 16, 0+shift, 0,0' `pidof sleep` # just PTRACE_ATTACH + exit [1]+ Stopped sleep 1000 $ grep State: /proc/`pidof sleep`/status State: T (stopped) This is the "normal" behaviour, afaics the same happens with init now. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html