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author | Oleg Nesterov <oleg@redhat.com> | 2024-01-27 16:24:07 +0300 |
---|---|---|
committer | Christian Brauner <brauner@kernel.org> | 2024-02-02 15:12:28 +0300 |
commit | 21e25205d7f9b6d7d3807546dd12ea93844b7c8e (patch) | |
tree | a108a353ed272200db1a876db45c22691118a755 | |
parent | cdefbf2324ceda662e2667aa2f44e8b9de3d780f (diff) | |
download | linux-21e25205d7f9b6d7d3807546dd12ea93844b7c8e.tar.xz |
pidfd: don't do_notify_pidfd() if !thread_group_empty()
do_notify_pidfd() makes no sense until the whole thread group exits, change
do_notify_parent() to check thread_group_empty().
This avoids the unnecessary do_notify_pidfd() when tsk is not a leader, or
it exits before other threads, or it has a ptraced EXIT_ZOMBIE sub-thread.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20240127132407.GA29136@redhat.com
Reviewed-by: Tycho Andersen <tandersen@netflix.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
-rw-r--r-- | kernel/signal.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/kernel/signal.c b/kernel/signal.c index c9c57d053ce4..9561a3962ca6 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2050,9 +2050,11 @@ bool do_notify_parent(struct task_struct *tsk, int sig) WARN_ON_ONCE(!tsk->ptrace && (tsk->group_leader != tsk || !thread_group_empty(tsk))); - - /* Wake up all pidfd waiters */ - do_notify_pidfd(tsk); + /* + * tsk is a group leader and has no threads, wake up the pidfd waiters. + */ + if (thread_group_empty(tsk)) + do_notify_pidfd(tsk); if (sig != SIGCHLD) { /* |