Merge tag 'locks-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

Pull file locking updates from Jeff Layton:
 "Just a couple of patches from Konstantin to fix /proc/locks when the
  process that set the lock has exited, and a new tracepoint for the
  flock() codepath. Also threw in mailmap entries for my addresses and a
  comment cleanup"

* tag 'locks-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  locks: remove misleading obsolete comment
  mailmap: remap some of my email addresses to kernel.org address
  locks: add tracepoint in flock codepath
  fs/lock: show locks taken by processes from another pidns
  fs/lock: skip lock owner pid translation in case we are in init_pid_ns

1 files changed, 11 insertions, 9 deletions

diff --git a/fs/locks.c b/fs/locks.c
index db7b6917d9c5..bc047a7edc47 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -202,10 +202,6 @@ static DEFINE_HASHTABLE(blocked_hash, BLOCKED_HASH_BITS);
  * we often hold the flc_lock as well. In certain cases, when reading the fields
  * protected by this lock, we can skip acquiring it iff we already hold the
  * flc_lock.
- *
- * In particular, adding an entry to the fl_block list requires that you hold
- * both the flc_lock and the blocked_lock_lock (acquired in that order).
- * Deleting an entry from the list however only requires the file_lock_lock.
  */
 static DEFINE_SPINLOCK(blocked_lock_lock);
 
@@ -990,6 +986,7 @@ out:
 	if (new_fl)
 		locks_free_lock(new_fl);
 	locks_dispose_list(&dispose);
+	trace_flock_lock_inode(inode, request, error);
 	return error;
 }
 
@@ -2072,6 +2069,13 @@ static pid_t locks_translate_pid(struct file_lock *fl, struct pid_namespace *ns)
 		return -1;
 	if (IS_REMOTELCK(fl))
 		return fl->fl_pid;
+	/*
+	 * If the flock owner process is dead and its pid has been already
+	 * freed, the translation below won't work, but we still want to show
+	 * flock owner pid number in init pidns.
+	 */
+	if (ns == &init_pid_ns)
+		return (pid_t)fl->fl_pid;
 
 	rcu_read_lock();
 	pid = find_pid_ns(fl->fl_pid, &init_pid_ns);
@@ -2626,12 +2630,10 @@ static void lock_get_status(struct seq_file *f, struct file_lock *fl,
 
 	fl_pid = locks_translate_pid(fl, proc_pidns);
 	/*
-	 * If there isn't a fl_pid don't display who is waiting on
-	 * the lock if we are called from locks_show, or if we are
-	 * called from __show_fd_info - skip lock entirely
+	 * If lock owner is dead (and pid is freed) or not visible in current
+	 * pidns, zero is shown as a pid value. Check lock info from
+	 * init_pid_ns to get saved lock pid value.
 	 */
-	if (fl_pid == 0)
-		return;
 
 	if (fl->fl_file != NULL)
 		inode = locks_inode(fl->fl_file);