From:   "inoguchi.yuki@fujitsu.com" <inoguchi.yuki@fujitsu.com>
To:     "'bfields@fieldses.org'" <bfields@fieldses.org>
CC:     'Trond Myklebust' <trondmy@hammerspace.com>,
        "'linux-nfs@vger.kernel.org'" <linux-nfs@vger.kernel.org>,
        "'neilb@suse.de'" <neilb@suse.de>,
        "'mbenjami@redhat.com'" <mbenjami@redhat.com>
Subject: RE: client caching and locks
Thread-Topic: client caching and locks
Thread-Index: AQHWPdqMcAycEC0/pke1JkGmPD8pPKjeL0EwgABO2QCAAF7SgIAF4BMAgJ9AToCAAArJgIAHh8GAgr9HWraACijNgIABG0CggAA4XwCAADEigIAABkSAgAEmVACAANM0gIAAmsvggAB08gCAATEf4A==
Date:   Fri, 7 Jan 2022 08:33:24 +0000
Deferred-Delivery: Fri, 7 Jan 2022 08:31:38 +0000
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> I could live with that.
>=20
> Though the other reason I cut it was because I think it needs updates
> too and I wasn't sure exactly how to handle them.
>
> The v4 case is more important and should probably be dealt with first.
> I think the answer there is just "don't mount /var over NFSv4", period.
>
> And maybe we should be more specific: the problem is with /var/lib/nfs,
> not all of /var.

I see it now. Yeah, I agree. If we keep that description, we need to consid=
er the v4 case ...

After reviewing what will happen if we delete this description for /var,
I've changed my mind. I believe it won't cause a serious problem.
I have concluded that it is no longer needed for the following reasons:

 1. Users who build a new system with NFSv2 or v3 are not so many nowadays.
 2. Even with the nolock option, mounting /var is risky. For example,=20
   if /var is mounted when the system is running, the existing processes wo=
uld
   be prevented from accessing the files they require.

In other words, I agree with your idea. Your first patch looks good to me.=
=20
I think we can remove the part "using nolock to mount /var with v2/v3" from=
 the nfs man page.=20

I apologize for taking your time.

Yuki Inoguchi