When a loop device is being shutdown the backing file is closed with fput(). This is different from how close(2) closes files - it uses filp_close(). The difference is important for filesystems which provide a ->flush file operation such as NFS. NFS assumes a flush will always be called on last close, and gets confused otherwise. Signed-off-by: NeilBrown <neilb@xxxxxxxx> --- drivers/block/loop.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index ebbd0c3fe0ed..9c457ca6c55e 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -682,7 +682,7 @@ static int loop_change_fd(struct loop_device *lo, struct block_device *bdev, if (error) goto out_putf; - fput(old_file); + filp_close(old_file, NULL); if (lo->lo_flags & LO_FLAGS_PARTSCAN) loop_reread_partitions(lo, bdev); return 0; @@ -1071,12 +1071,12 @@ static int loop_clr_fd(struct loop_device *lo) loop_unprepare_queue(lo); mutex_unlock(&lo->lo_ctl_mutex); /* - * Need not hold lo_ctl_mutex to fput backing file. + * Need not hold lo_ctl_mutex to close backing file. * Calling fput holding lo_ctl_mutex triggers a circular * lock dependency possibility warning as fput can take * bd_mutex which is usually taken before lo_ctl_mutex. */ - fput(filp); + filp_close(filp, NULL); return 0; }