libmount: revert "read mtab on remount" idea

It's backwardly incompatible nonsense to prefer mtab on remount.

 mount -o remount /foo

has to read mount options from fstab otherwise the remount has no
effect. (The ideal solution would be to read both mtab, then modify
the options according to fstab -- but for now more important is to be
backwardly compatible.)

References: https://bugzilla.redhat.com/show_bug.cgi?id=1182778
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libmount/src/context.c b/libmount/src/context.c
index 14fa44b52e49b0da91203ee38b227b408f623fc4..f623f34a77eef900e201f9e61de38d17e5cc94e0 100644 (file)
--- a/libmount/src/context.c
+++ b/libmount/src/context.c
@@ -2051,13 +2051,8 @@ int mnt_context_apply_fstab(struct libmnt_context *cxt)
                cxt->optsmode &= ~MNT_OMODE_FORCE;
        }
 
-       if (mnt_context_get_mflags(cxt, &mflags) == 0 && mflags & MS_REMOUNT) {
-               /* preffer mtab on remount */
-               DBG(CXT, ul_debugobj(cxt, "force mtab parsing on remount"));
-               cxt->optsmode |= MNT_OMODE_MTAB;
-               cxt->optsmode &= ~MNT_OMODE_FSTAB;
+       if (mnt_context_get_mflags(cxt, &mflags) == 0 && mflags & MS_REMOUNT)
                isremount = 1;
-       }
 
        if (cxt->fs) {
                src = mnt_fs_get_source(cxt->fs);

diff --git a/sys-utils/mount.8 b/sys-utils/mount.8
index 854268a31f6bd99e415aa683a88adbf5e408ca16..69412167da9d8fc9d6f8196e5412462e1c1f27da 100644 (file)
--- a/sys-utils/mount.8
+++ b/sys-utils/mount.8
@@ -1070,10 +1070,9 @@ Attempt to remount an already-mounted filesystem.  This is commonly
 used to change the mount flags for a filesystem, especially to make a
 readonly filesystem writable.  It does not change device or mount point.
 
-The remount functionality follows the standard way the mount command works with
-options, but preferred source for the options is mtab (or /proc/self/mouninfo)
-rather than fstab.  The mount command only does not read mtab 
-when both the
+The remount functionality follows the standard way the mount command works
+with options from fstab.  This means that the mount command only doesn't
+read fstab (or mtab) when both the
 .I device
 and
 .I dir
@@ -1082,16 +1081,16 @@ are specified.
 .B "mount \-o remount,rw /dev/foo /dir"
 
 After this call all old mount options are replaced and arbitrary stuff from
-mtab is ignored, except the loop= option which is internally generated and
-maintained by the mount command.
+fstab (or mtab) is ignored, except the loop= option which is internally
+generated and maintained by the mount command.
 
 .B "mount \-o remount,rw  /dir"
 
-After this call mount reads mtab and merges these options with
+After this call mount reads fstab and merges these options with
 the options from the command line (\c
 .B \-o\c
-). If no mtab (or /proc/self/mountinfo) is available than remount with unspecified
-source is allowed.
+). If no mountpoint found in fstab than remount with unspecified source is
+allowed.
 .TP
 .B ro
 Mount the filesystem read-only.