Again, adding Oleg to the cc. And I don't think this is correct, since SIGKILL can actually kill uninterruptible processes too (TASK_WAKEKILL) so the basic premise of the patch is incorrect. And again, we do have that whole issue with exit_mm() serialization.
Linus On Sat, Dec 21, 2013 at 4:18 AM, Vaibhav Shinde <v.bhav.shi...@gmail.com> wrote: > Dear All, > > We found below issue in coredump for uninterruptible task - > > From 1c46f0327d98ad593d8913f9f1dad352f8f44304 Mon Sep 17 00:00:00 2001 > From: Ajeet Yadav <ajeet.yadav...@gmail.com> > Date: Sat, 21 Dec 2013 17:06:05 +0530 > Subject: [PATCH] skip increamenting nr for TASK_UNINTERRUPTIBLE > > In coredump case, where thread_1 faults while thread_2 is in > TASK_UNINTERRUPTIBLE state, it cannot handle the SIGKILL. > Thus the process hangs on event. > The coredump routine freezes until the thread state is > uninterruptible. > > Solution: Continue for coredump, without waiting for uninterruptible > thread, as it will get killed as soon as it returns from > uninterruptible state. > Therefore do not increament thread count for threads with > TASK_UNINTERRUPTIBLE. > > Signed-off-by: Ajeet Yadav <ajeet.yadav...@gmail.com> > Signed-off-by: Vaibhav Shinde <v.bhav.shi...@gmail.com> > --- > fs/coredump.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletions(-) > > diff --git a/fs/coredump.c b/fs/coredump.c > index 447b02c..54b0664 100644 > --- a/fs/coredump.c > +++ b/fs/coredump.c > @@ -281,7 +281,8 @@ static int zap_process(struct task_struct *start, > int exit_code) > if (t != current && t->mm) { > sigaddset(&t->pending.signal, SIGKILL); > signal_wake_up(t, 1); > - nr++; > + if(!(t->state & TASK_UNINTERRUPTIBLE)) > + nr++; > } > } while_each_thread(start, t); > > -- > 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/