Hi Li,
On Wed, Nov 13, 2024 at 11:33 PM Li Lingfeng <lilingfeng3@xxxxxxxxxx> wrote:
>
> During the process of mounting an NFSv4 client, two superblocks will be
> created in sequence. The first superblock corresponds to the root
> directory exported by the server, and the second superblock corresponds to
> the directory that will be actually mounted. The first superblock will
> eventually be destroyed.
> The flag passed from user mode will only be passed to the first
> superblock, resulting in the actual used superblock not carrying the flag
> passed from user mode(fs_context_for_submount() will set sb_flags as 0).
>
> Since the superblock of NFS does not carry the ro tag, the file system
> status displayed by /proc/self/mountstats shows that NFS is always in the
> rw state, which may mislead users.
>
> Pass sb_flags of the fc which carry flags passed by user to second
> superblock to fix it.
>
> Fixes: 281cad46b34d ("NFS: Create a submount rpc_op")
> Signed-off-by: Li Lingfeng <lilingfeng3@xxxxxxxxxx>
> ---
> fs/nfs/nfs4super.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/fs/nfs/nfs4super.c b/fs/nfs/nfs4super.c
> index b29a26923ce0..9a3b73a33fbf 100644
> --- a/fs/nfs/nfs4super.c
> +++ b/fs/nfs/nfs4super.c
> @@ -233,6 +233,7 @@ static int do_nfs4_mount(struct nfs_server *server,
> if (IS_ERR(dentry))
> return PTR_ERR(dentry);
>
> + dentry->d_sb->s_flags = fc->sb_flags;
I'm seeing a handful of new xfstests failures that I bisected to this
patch: generic/157, generic/184, generic/306, generic/564, and
generic/598.
I'm seeing this on NFS v4.1 and v4.2, and it looks like each one of
these failures is due to a new -EIO error being generated. Any
thoughts about what could be causing this?
Thanks,
Anna
> fc->root = dentry;
> return 0;
> }
> --
> 2.31.1
>
