From: Oleg Nesterov Date: Thu, 2 Apr 2009 23:58:15 +0000 (-0700) Subject: reparent_thread: don't call kill_orphaned_pgrp() if task_detached() X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=0a967a044a777e8b9c739120927114ddc0094298;p=linux-2.6-omap-h63xx.git reparent_thread: don't call kill_orphaned_pgrp() if task_detached() If task_detached(p) == T, then either a) p is not the main thread, we will find the group leader on the ->children list. or b) p is the group leader but its ->exit_state = EXIT_DEAD. This can only happen when the last sub-thread has died, but in that case that thread has already called kill_orphaned_pgrp() from exit_notify(). In both cases kill_orphaned_pgrp() looks bogus. Move the task_detached() check up and simplify the code, this is also right from the "common sense" pov: we should do nothing with the detached childs, except move them to the new parent's ->children list. Signed-off-by: Oleg Nesterov Cc: Roland McGrath Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/kernel/exit.c b/kernel/exit.c index 576eae233b5..405e6877168 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -818,6 +818,8 @@ static void reparent_thread(struct task_struct *p, struct task_struct *father) list_move_tail(&p->sibling, &p->real_parent->children); + if (task_detached(p)) + return; /* If this is a threaded reparent there is no need to * notify anyone anything has happened. */ @@ -825,15 +827,13 @@ static void reparent_thread(struct task_struct *p, struct task_struct *father) return; /* We don't want people slaying init. */ - if (!task_detached(p)) - p->exit_signal = SIGCHLD; + p->exit_signal = SIGCHLD; /* If we'd notified the old parent about this child's death, * also notify the new parent. */ if (!ptrace_reparented(p) && - p->exit_state == EXIT_ZOMBIE && - !task_detached(p) && thread_group_empty(p)) + p->exit_state == EXIT_ZOMBIE && thread_group_empty(p)) do_notify_parent(p, p->exit_signal); kill_orphaned_pgrp(p, father);