From 45a68628d37222e655219febce9e91b6484789b2 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 23 Mar 2011 16:43:12 -0700 Subject: pid: remove the child_reaper special case in init/main.c This patchset is a cleanup and a preparation to unshare the pid namespace. These prerequisites prepare for Eric's patchset to give a file descriptor to a namespace and join an existing namespace. This patch: It turns out that the existing assignment in copy_process of the child_reaper can handle the initial assignment of child_reaper we just need to generalize the test in kernel/fork.c Signed-off-by: Eric W. Biederman Signed-off-by: Daniel Lezcano Cc: Oleg Nesterov Cc: Alexey Dobriyan Acked-by: Serge E. Hallyn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pid.h | 11 +++++++++++ init/main.c | 9 --------- kernel/fork.c | 2 +- 3 files changed, 12 insertions(+), 10 deletions(-) diff --git a/include/linux/pid.h b/include/linux/pid.h index 49f1c2f66e95..efceda0a51b1 100644 --- a/include/linux/pid.h +++ b/include/linux/pid.h @@ -140,6 +140,17 @@ static inline struct pid_namespace *ns_of_pid(struct pid *pid) return ns; } +/* + * is_child_reaper returns true if the pid is the init process + * of the current namespace. As this one could be checked before + * pid_ns->child_reaper is assigned in copy_process, we check + * with the pid number. + */ +static inline bool is_child_reaper(struct pid *pid) +{ + return pid->numbers[pid->level].nr == 1; +} + /* * the helpers to get the pid's id seen from different namespaces * diff --git a/init/main.c b/init/main.c index 3627bb37225c..4a9479ef4540 100644 --- a/init/main.c +++ b/init/main.c @@ -787,15 +787,6 @@ static int __init kernel_init(void * unused) * init can run on any cpu. */ set_cpus_allowed_ptr(current, cpu_all_mask); - /* - * Tell the world that we're going to be the grim - * reaper of innocent orphaned children. - * - * We don't want people to have to make incorrect - * assumptions about where in the task array this - * can be found. - */ - init_pid_ns.child_reaper = current; cad_pid = task_pid(current); diff --git a/kernel/fork.c b/kernel/fork.c index f2b494d7c557..17aed4378eda 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1296,7 +1296,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, tracehook_finish_clone(p, clone_flags, trace); if (thread_group_leader(p)) { - if (clone_flags & CLONE_NEWPID) + if (is_child_reaper(pid)) p->nsproxy->pid_ns->child_reaper = p; p->signal->leader_pid = pid; -- cgit v1.2.3-59-g8ed1b