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From:   "Benjamin Coddington" <bcodding@redhat.com>
To:     "Trond Myklebust" <trondmy@hammerspace.com>
Cc:     mwakabayashi@vmware.com, linux-nfs@vger.kernel.org, aglo@umich.edu,
        SteveD@redhat.com
Subject: Re: NFSv4: Mounting NFS server which is down, blocks all other NFS
 mounts on same machine
Date:   Wed, 09 Jun 2021 11:00:21 -0400
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On 9 Jun 2021, at 10:41, Trond Myklebust wrote:

> On Wed, 2021-06-09 at 10:31 -0400, Benjamin Coddington wrote:
>>
>> It's not disputed that mounts waiting on the transport layer will block
>> other mounts.
>>
>> It might be able to be changed:  there's this torch:
>> https://lore.kernel.org/linux-nfs/87378omld4.fsf@notabene.neil.brown.name/
>>
>
> No.
>
>> ..or there may be another way we don't have to wait ..
>>
>
> OK. So let's look at how we can solve the problem of the initial
> connection to the server timing out and causing hangs in
> nfs41_walk_client_list(), and leave aside any other corner case
> problems (such as the server going down while we're mounting).
>
> How about something like the following (compile tested only) patch?

It works as intended for this case, but I don't have my head wrapped around
the implications of the change yet.

Ben