tree 5ba019b857b23212a0c30aeb24f7a3f54b568b51
parent 6b31d5955cb29a51c5baffee382f213d75e98fb8
author Jamie Iles <jamie.iles@oracle.com> 1503094578 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1503095522 -0700

signal: don't remove SIGNAL_UNKILLABLE for traced tasks.

When forcing a signal, SIGNAL_UNKILLABLE is removed to prevent recursive
faults, but this is undesirable when tracing.  For example, debugging an
init process (whether global or namespace), hitting a breakpoint and
SIGTRAP will force SIGTRAP and then remove SIGNAL_UNKILLABLE.
Everything continues fine, but then once debugging has finished, the
init process is left killable which is unlikely what the user expects,
resulting in either an accidentally killed init or an init that stops
reaping zombies.

Link: http://lkml.kernel.org/r/20170815112806.10728-1-jamie.iles@oracle.com
Signed-off-by: Jamie Iles <jamie.iles@oracle.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>