lock_task_sighand() conditionally acquires sighand->siglock in case of
returning non-NULL but unlock_task_sighand() releases it unconditionally.
This leads sparse to complain about the lock context imbalance. Annotate it
to make sparse happier.
Impact: remove sparse warnings, no runtime overhead.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
---
kernel/signal.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/kernel/signal.c b/kernel/signal.c
index bded651..c423fc5 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1038,6 +1038,7 @@ int do_send_sig_info(int sig, struct siginfo *info, struct task_struct *p,
int ret = -ESRCH;
if (lock_task_sighand(p, &flags)) {
+ __acquire(&p->sighand->siglock);
ret = send_signal(sig, info, p, group);
unlock_task_sighand(p, &flags);
}
@@ -1227,6 +1228,7 @@ int kill_pid_info_as_uid(int sig, struct siginfo *info, struct pid *pid,
if (sig) {
if (lock_task_sighand(p, &flags)) {
+ __acquire(&p->sighand->siglock);
ret = __send_signal(sig, info, p, 1, 0);
unlock_task_sighand(p, &flags);
} else
@@ -1406,6 +1408,8 @@ int send_sigqueue(struct sigqueue *q, struct task_struct *t, int group)
if (!likely(lock_task_sighand(t, &flags)))
goto ret;
+ __acquire(&t->sighand->siglock);
+
ret = 1; /* the signal is ignored */
if (!prepare_signal(sig, t, 0))
goto out;
--
1.7.0.4
--
