commit 0e64123141f3854e695eb4924d82b52856691466
author Olivier Deprez <olivier.deprez@arm.com> Thu Sep 23 10:07:05 2021 +0200
committer Olivier Deprez <olivier.deprez@arm.com> Tue Oct 26 16:50:53 2021 +0100
tree 9f79e140db584f9b107f4e33373a0075983df1f4
parent 98854e9675dc7d951fa9c4e10d9c9d230c54bde6

Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>

kernel/kcmp.c

diff --git a/kernel/kcmp.c b/kernel/kcmp.c
index a0e3d7a..c0d2ad9 100644
--- a/kernel/kcmp.c
+++ b/kernel/kcmp.c
@@ -75,25 +75,25 @@
 	return file;
 }
 
-static void kcmp_unlock(struct mutex *m1, struct mutex *m2)
+static void kcmp_unlock(struct rw_semaphore *l1, struct rw_semaphore *l2)
 {
-	if (likely(m2 != m1))
-		mutex_unlock(m2);
-	mutex_unlock(m1);
+	if (likely(l2 != l1))
+		up_read(l2);
+	up_read(l1);
 }
 
-static int kcmp_lock(struct mutex *m1, struct mutex *m2)
+static int kcmp_lock(struct rw_semaphore *l1, struct rw_semaphore *l2)
 {
 	int err;
 
-	if (m2 > m1)
-		swap(m1, m2);
+	if (l2 > l1)
+		swap(l1, l2);
 
-	err = mutex_lock_killable(m1);
-	if (!err && likely(m1 != m2)) {
-		err = mutex_lock_killable_nested(m2, SINGLE_DEPTH_NESTING);
+	err = down_read_killable(l1);
+	if (!err && likely(l1 != l2)) {
+		err = down_read_killable_nested(l2, SINGLE_DEPTH_NESTING);
 		if (err)
-			mutex_unlock(m1);
+			up_read(l1);
 	}
 
 	return err;
@@ -173,8 +173,8 @@
 	/*
 	 * One should have enough rights to inspect task details.
 	 */
-	ret = kcmp_lock(&task1->signal->cred_guard_mutex,
-			&task2->signal->cred_guard_mutex);
+	ret = kcmp_lock(&task1->signal->exec_update_lock,
+			&task2->signal->exec_update_lock);
 	if (ret)
 		goto err;
 	if (!ptrace_may_access(task1, PTRACE_MODE_READ_REALCREDS) ||
@@ -229,8 +229,8 @@
 	}
 
 err_unlock:
-	kcmp_unlock(&task1->signal->cred_guard_mutex,
-		    &task2->signal->cred_guard_mutex);
+	kcmp_unlock(&task1->signal->exec_update_lock,
+		    &task2->signal->exec_update_lock);
 err:
 	put_task_struct(task1);
 	put_task_struct(task2);