Re: [nfs-utils PATCH] retry on EPERM from NFSv4 mount attempt

[Steve Dickson <SteveD@redhat.com>]

On 11/23/2009 06:32 PM, Neil Brown wrote:
> 
> Hi,
>  I recently packaged nfs-utils 1.2.1 for openSUSE and fairly quickly
>  got a bug report - "-o nfsvers=3" was needed to mount NFSv3
>  filesystems.
> 
>  mount.nfs in 1.2.1 will first try a v4 mount but will fall-back to v3
>  if it gets ENOENT.  This works fine.
>  However for kernel prior to 2.6.25, you don't get ENOENT, you get
>  EPERM.
>  In that case the fall-back to v3 doesn't happen and you get a failure
>  to mount.
> 
>  So I think we need to fall back on EPERM as well.  See below.
I already posted this patch on the v4 mailing list
http://linux-nfs.org/pipermail/nfsv4/2009-November/011595.html
but it got shot down...  at least that's how I interpreted the
responses... 

But I do thing we need this, since there are so many server 
that will simple break if we don't... Agreed?

steved. 


> 
> Thanks,
> NeilBrown
> 
> 
> diff --git a/utils/mount/stropts.c b/utils/mount/stropts.c
> index b595649..68eb82b 100644
> --- a/utils/mount/stropts.c
> +++ b/utils/mount/stropts.c
> @@ -657,8 +657,10 @@ static int nfs_try_mount(struct nfsmount_info *mi)
>  				 * To deal with legacy Linux servers that don't
>  				 * automatically export a pseudo root, retry
>  				 * ENOENT errors using version 3
> +				 * And for Linux servers prior to 2.6.25, retry
> +				 * EPERM
>  				 */
> -				if (errno != ENOENT)
> +				if (errno != ENOENT && errno != EPERM)
>  					break;
>  			}
>  		}