Merge tag 'backlight-for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / init / Kconfig

diff --git a/init/Kconfig b/init/Kconfig
index ba1e6ea..bb9b4dd 100644 (file)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -947,6 +947,22 @@ config CGROUP_FREEZER
          Provides a way to freeze and unfreeze all tasks in a
          cgroup.
 
+config CGROUP_PIDS
+       bool "PIDs cgroup subsystem"
+       help
+         Provides enforcement of process number limits in the scope of a
+         cgroup. Any attempt to fork more processes than is allowed in the
+         cgroup will fail. PIDs are fundamentally a global resource because it
+         is fairly trivial to reach PID exhaustion before you reach even a
+         conservative kmemcg limit. As a result, it is possible to grind a
+         system to halt without being limited by other cgroup policies. The
+         PIDs cgroup subsystem is designed to stop this from happening.
+
+         It should be noted that organisational operations (such as attaching
+         to a cgroup hierarchy will *not* be blocked by the PIDs subsystem),
+         since the PIDs limit only affects a process's ability to fork, not to
+         attach to a cgroup.
+
 config CGROUP_DEVICE
        bool "Device controller for cgroups"
        help