From 24646481fb19a3bd86933ec30480454381ff9860 Mon Sep 17 00:00:00 2001 From: Leon Romanovsky Date: Wed, 19 Aug 2020 17:16:28 +0300 Subject: [PATCH] btrfs: sysfs: fix unused-but-set-variable warnings The compilation with W=1 generates the following warnings: fs/btrfs/sysfs.c:1630:6: warning: variable 'ret' set but not used [-Wunused-but-set-variable] 1630 | int ret; | ^~~ fs/btrfs/sysfs.c:1629:6: warning: variable 'features' set but not used [-Wunused-but-set-variable] 1629 | u64 features; | ^~~~~~~~ [ The unused variables are leftover from e410e34fad91 ("Revert "btrfs: synchronize incompat feature bits with sysfs files""), which needs to be properly fixed by moving feature bit manipulation from the sysfs context. Silence the warning to save pepople time, we got several reports. ] Signed-off-by: Leon Romanovsky Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/sysfs.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c index fcc8757b4e93..81496ac43d09 100644 --- a/fs/btrfs/sysfs.c +++ b/fs/btrfs/sysfs.c @@ -1630,12 +1630,16 @@ void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info, { struct btrfs_fs_devices *fs_devs; struct kobject *fsid_kobj; - u64 features; - int ret; + u64 __maybe_unused features; + int __maybe_unused ret; if (!fs_info) return; + /* + * See 14e46e04958df74 and e410e34fad913dd, feature bit updates are not + * safe when called from some contexts (eg. balance) + */ features = get_features(fs_info, set); ASSERT(bit & supported_feature_masks[set]);