Re: [PATCH v13 7/7] ntfs: fail remount on sync errors and keep the dirty bit on SB_FORCE

[liubaolin]

在 2026/9/15 16:32, Hongling Zeng 写道:
> ntfs_reconfigure() currently ignores sync_filesystem() errors, allowing
> a regular read-only remount to succeed even when dirty data was not
> synced. Check the error and fail regular remounts, leaving the
> superblock read-write so ntfs_put_super() can retry at unmount.
>
> SB_FORCE does not wait for writers already in progress, so it must not
> clear the on-disk dirty bit. Warn and continue on sync errors for
> SB_FORCE. A forced remount updates the dirty state only when errors
> have been recorded, and never clears the dirty bit. Skip the commit if
> that state update fails, since the in-memory flags may be inconsistent.
>
> Reported-by: Hyunchul Lee <hyc.lee@xxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Hongling Zeng <zenghongling@xxxxxxxxxx>
> ---
>   fs/ntfs/super.c | 27 +++++++++++++++++++++------
>   1 file changed, 21 insertions(+), 6 deletions(-)
>
> diff --git a/fs/ntfs/super.c b/fs/ntfs/super.c
> index 0228d7429596..82b5bf28b6ab 100644
> --- a/fs/ntfs/super.c
> +++ b/fs/ntfs/super.c
> @@ -272,7 +272,13 @@ static int ntfs_reconfigure(struct fs_context *fc)
>   
>   	ntfs_debug("Entering with remount");
>   
> -	sync_filesystem(sb);
> +	err = sync_filesystem(sb);
> +	if (err) {
> +		ntfs_warning(sb, "Failed to sync the filesystem.");
> +		/* A forced remount must still turn the superblock read-only. */
> +		if (!(fc->sb_flags & SB_FORCE))
> +			return err;
> +	}
>   
>   	/*
>   	 * For the read-write compiled driver, if we are remounting read-write,
> @@ -329,11 +335,20 @@ static int ntfs_reconfigure(struct fs_context *fc)
>   		 * or flush fails the remount, leaving the superblock
>   		 * read-write so ntfs_put_super() retries at unmount.
>   		 */
> -		err = ntfs_sync_volume_dirty_state(vol);
> -		if (err) {
> -			ntfs_warning(sb,
> -				"Failed to update dirty bit in volume information flags.  Run chkdsk.");
> -			return err;
> +		/*
> +		 * A forced remount does not drain writers in progress,
> +		 * so one may still be modifying metadata when the flags
> +		 * are committed: never clear the dirty bit then; if
> +		 * errors have been recorded, the update preserves or
> +		 * sets it; otherwise, skip the update entirely.
> +		 */
> +		if (!(fc->sb_flags & SB_FORCE) || NVolErrors(vol)) {
> +			err = ntfs_sync_volume_dirty_state(vol);
> +			if (err) {
> +				ntfs_warning(sb,
> +					"Failed to update dirty bit in volume information flags.  Run chkdsk.");
> +				return err;
> +			}
>   		}
>   		if (NInoDirty(NTFS_I(vol->vol_ino))) {
>   			/* ntfs_commit_inode() would discard the error. */

Looks good to me.

Reviewed-by: Baolin Liu <liubaolin@xxxxxxxxxx>