Add DEVPTS_MULTIPLE_INSTANCES config token

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index c602b547cc6e08afd842182b80fac140c13766cb..c52a167227e7c7173be5faadfb441781abc0abff 100644 (file)
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -443,6 +443,17 @@ config UNIX98_PTYS
          All modern Linux systems use the Unix98 ptys.  Say Y unless
          you're on an embedded system and want to conserve memory.
 
+config DEVPTS_MULTIPLE_INSTANCES
+       bool "Support multiple instances of devpts"
+       depends on UNIX98_PTYS
+       default n
+       ---help---
+         Enable support for multiple instances of devpts filesystem.
+         If you want to have isolated PTY namespaces (eg: in containers),
+         say Y here.  Otherwise, say N. If enabled, each mount of devpts
+         filesystem with the '-o newinstance' option will create an
+         independent PTY namespace.
+
 config LEGACY_PTYS
        bool "Legacy (BSD) PTY support"
        default y