Chuck Lever schrieb am Di 09. Dez, 19:28 (-0500):
> From: Chuck Lever <chuck.lever@oracle.com>
> 
> A documenting comment in include/uapi/linux/nfs.h claims incorrectly
> that NFSv2 defines NFSERR_INVAL. There is no such definition in either
> RFC 1094 or https://pubs.opengroup.org/onlinepubs/9629799/chap7.htm
> 
> NFS3ERR_INVAL is introduced in RFC 1813.

Hello,

since this commit 0ac903d1bfdce8ff40657c2b7d996947b72b6645 was added, U-Boot
2022.04 (I don't know about newer versions) can no longer access symlinks in
NFS shares. When I revert this commit, U-Boot can load the file behind the
symlink. Real files are no problem.

The file I want to load is a symlink at the server:

```
% ls -l /srv/nfs/boot/Image.gz*
lrwxrwxrwx 1 root root      41  7. Jul 16:29 /srv/nfs-con/boot/Image.gz -> Image.gz-5.15.213-imx8mm+gfffa4b6d4aea+p1
-rw-r--r-- 1 root root 5279373  7. Jul 16:29 /srv/nfs-con/boot/Image.gz-5.15.213-imx8mm+gfffa4b6d4aea+p1
```

Without this commit:

```
u-boot=> nfs 0x42000000 /srv/nfs/boot/Image.gz
Filename '/srv/nfs-con/boot/Image.gz'.
Load address: 0x42000000
Loading: #################################################################
done
Bytes transferred = 5279373 (508e8d hex)
```

But with this commit:

```
u-boot=> nfs 0x42000000 /srv/nfs/boot/Image.gz
Filename '/srv/nfs-con/boot/Image.gz'.
Load address: 0x42000000
Loading:
done
```

This is the network traffic:

```
No.	Time	Protocol	Length	Info
3	0.000370	Portmap	98	V2 GETPORT Call (Reply In 4) MOUNT(100005) V:1 UDP
4	0.000607	Portmap	70	V2 GETPORT Reply (Call In 3) Port:60340
5	0.000949	Portmap	98	V2 GETPORT Call (Reply In 6) NFS(100003) V:2 UDP
6	0.001046	Portmap	70	V2 GETPORT Reply (Call In 5) Port:2049
7	0.001368	MOUNT	126	V2 MNT Call (Reply In 8) /srv/nfs-con/boot
8	0.008026	MOUNT	102	V2 MNT Reply (Call In 7)
9	0.008389	NFS	146	V2 LOOKUP Call (Reply In 10), DH: 0x8c279135/Image.gz
10	0.008754	NFS	170	V2 LOOKUP Reply (Call In 9), FH: 0xcdddf154
11	0.009095	NFS	146	V2 READ Call (Reply In 12), FH: 0xcdddf154 Offset: 0 Count: 1024 TotalCount: 0
12	0.009189	NFS	70	V2 READ Reply (Call In 11) Error: NFS2ERR_IO
13	0.009511	MOUNT	102	V2 UMNTALL Call (Reply In 14)
14	0.010301	MOUNT	66	V2 UMNTALL Reply (Call In 13)
```

From packet 11 V2 READ Call

```
Remote Procedure Call, Type:Call XID:0x000050e1
    XID: 0x000050e1 (20705)
    Message Type: Call (0)
    RPC Version: 2
    Program: NFS (100003)
    Program Version: 2
    Procedure: READ (6)
    [The reply to this request is in frame 12]
    Credentials
        Flavor: AUTH_UNIX (1)
        Length: 20
        Stamp: 0x00000000
        Machine Name: <EMPTY>
        UID: 0
        GID: 0
        Auxiliary GIDs (0)
    Verifier
        Flavor: AUTH_NULL (0)
        Length: 0
Network File System, READ Call FH: 0xcdddf154 Offset: 0 Count: 1024 TotalCount: 0
    [Program Version: 2]
    [V2 Procedure: READ (6)]
    file
        [hash (CRC-32): 0xcdddf154]
        FileHandle: 010004010100540020bb3809040054002f2edde4000000000000000000000000
    Offset: 0
    Count: 1024
    Total Count: 0
```

From packet 12 V2 READ Reply

```
Remote Procedure Call, Type:Reply XID:0x000050e1
    XID: 0x000050e1 (20705)
    Message Type: Reply (1)
    [Program: NFS (100003)]
    [Program Version: 2]
    [Procedure: READ (6)]
    Reply State: accepted (0)
    [This is a reply to a request in frame 11]
    [Time from request: 94.000 microseconds]
    Verifier
        Flavor: AUTH_NULL (0)
        Length: 0
    Accept State: RPC executed successfully (0)
Network File System, READ Reply  Error: NFS2ERR_IO
    [Program Version: 2]
    [V2 Procedure: READ (6)]
    Status: NFS2ERR_IO (5)
```


I can locally revert this commit in our kernel, but is there any other way
to get it working again?


Thanks in advance.

Best regards Jörg

-- 
Optimisten haben gar keine Ahnung von den freudigen Überraschungen, die
Pessimisten erleben.
                                                (Peter Bramm)