From: Thomas Gleixner Date: Sat, 8 Mar 2025 16:48:43 +0000 (+0100) Subject: posix-timers: Make per process list RCU safe X-Git-Tag: v6.15-rc1~204^2~6 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=451898ea422b5861d95089d8d9c2a0ab8383775e;p=thirdparty%2Flinux.git posix-timers: Make per process list RCU safe Preparatory change to remove the sighand locking from the /proc/$PID/timers iterator. Signed-off-by: Thomas Gleixner Reviewed-by: Frederic Weisbecker Link: https://lore.kernel.org/all/20250308155624.403223080@linutronix.de --- diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index e4c92f42fa574..b917a162d84a1 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -518,7 +518,7 @@ static int do_timer_create(clockid_t which_clock, struct sigevent *event, * Store the unmodified signal pointer to make it valid. */ WRITE_ONCE(new_timer->it_signal, current->signal); - hlist_add_head(&new_timer->list, ¤t->signal->posix_timers); + hlist_add_head_rcu(&new_timer->list, ¤t->signal->posix_timers); } /* * After unlocking @new_timer is subject to concurrent removal and @@ -1004,7 +1004,7 @@ static void posix_timer_delete(struct k_itimer *timer) unsigned long sig = (unsigned long)timer->it_signal | 1UL; WRITE_ONCE(timer->it_signal, (struct signal_struct *)sig); - hlist_del(&timer->list); + hlist_del_rcu(&timer->list); posix_timer_cleanup_ignored(timer); }