From 74ed673c59598618c56131a6f1e656cbaaf0a3c8 Mon Sep 17 00:00:00 2001
From: Michael Kerrisk <mtk.manpages@gmail.com>
Date: Fri, 13 Aug 2021 22:56:30 +0200
Subject: [PATCH] mount.2: ERRORS: add EPERM error for case where a mount is
 locked

Refer the reader to mount_namespaces(7) for details.

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
---
 man2/mount.2 | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/man2/mount.2 b/man2/mount.2
index defcbb25f..2f184f9b5 100644
--- a/man2/mount.2
+++ b/man2/mount.2
@@ -824,6 +824,21 @@ is out of range.
 .B EPERM
 The caller does not have the required privileges.
 .TP
+.B EPERM
+An attempt was made to modify
+.RB ( MS_REMOUNT )
+the
+.BR MS_RDONLY ,
+.BR MS_NOSUID ,
+or
+.BR MS_NOEXEC
+flag, or one of the "atime" flags
+.RB ( MS_NOATIME ,
+.BR MS_NODIRATIME ,
+.BR MS_RELATIME )
+of an existing mount, but the mount is locked; see
+.BR mount_namespaces (7).
+.TP
 .B EROFS
 Mounting a read-only filesystem was attempted without giving the
 .B MS_RDONLY