From: Christian Brauner <christian.brauner@xxxxxxxxxx> The CLONE_PARENT flag cannot but used by init processes. Let's mention this in the manpages to prevent suprises. Signed-off-by: Christian Brauner <christian.brauner@xxxxxxxxxx> --- man2/clone.2 | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/man2/clone.2 b/man2/clone.2 index f0f29d6f1..aa98ab79b 100644 --- a/man2/clone.2 +++ b/man2/clone.2 @@ -646,6 +646,13 @@ if .B CLONE_PARENT is set, then the parent of the calling process, rather than the calling process itself, will be signaled. +.IP +The kernel will not allow global init and init processes in pid +namespaces to use the +.B CLONE_PARENT +flag. This is done to prevent the creation of multi-rooted process +trees. It also avoids unreapable zombies in the initial pid +namespace. .TP .BR CLONE_PARENT_SETTID " (since Linux 2.5.49)" Store the child thread ID at the location pointed to by -- 2.24.0
