On Wed, Feb 26, 2025 at 11:18:49AM -0800, Paul E. McKenney wrote: > The next-20250226 release gets an uninitialized-variable warning from the > move_mount syscall in builds with clang 19.1.5. This variable is in fact > assigned only if the MOVE_MOUNT_F_EMPTY_PATH flag is set, but is then > unconditionally passed to getname_maybe_null(), which unconditionally > references it. > > This patch simply sets uflags to zero in the same manner as is done > for lflags, which makes rcutorture happy, but might or might not be a > proper patch. > > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx> > Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx> > Cc: Christian Brauner <brauner@xxxxxxxxxx> > Cc: Jan Kara <jack@xxxxxxx> > Cc: <linux-fsdevel@xxxxxxxxxxxxxxx> > Cc: <linux-kernel@xxxxxxxxxxxxxxx> > --- Hey Paul! Thank you for the patch. The fix is correct but I've already taken a patch from Arnd yesterday. So hopefully you'll forgive me for not taking yours. :) > namespace.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/fs/namespace.c b/fs/namespace.c > index 663bacefddfa6..80505d533cd23 100644 > --- a/fs/namespace.c > +++ b/fs/namespace.c > @@ -4617,6 +4617,7 @@ SYSCALL_DEFINE5(move_mount, > if (flags & MOVE_MOUNT_BENEATH) mflags |= MNT_TREE_BENEATH; > > lflags = 0; > + uflags = 0; > if (flags & MOVE_MOUNT_F_SYMLINKS) lflags |= LOOKUP_FOLLOW; > if (flags & MOVE_MOUNT_F_AUTOMOUNTS) lflags |= LOOKUP_AUTOMOUNT; > if (flags & MOVE_MOUNT_F_EMPTY_PATH) uflags = AT_EMPTY_PATH; > @@ -4625,6 +4626,7 @@ SYSCALL_DEFINE5(move_mount, > return PTR_ERR(from_name); > > lflags = 0; > + uflags = 0; > if (flags & MOVE_MOUNT_T_SYMLINKS) lflags |= LOOKUP_FOLLOW; > if (flags & MOVE_MOUNT_T_AUTOMOUNTS) lflags |= LOOKUP_AUTOMOUNT; > if (flags & MOVE_MOUNT_T_EMPTY_PATH) uflags = AT_EMPTY_PATH;
