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Date:   Tue, 3 Oct 2023 11:03:58 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Lorenzo Bianconi <lorenzo@kernel.org>
Cc:     linux-nfs@vger.kernel.org, lorenzo.bianconi@redhat.com,
        chuck.lever@oracle.com, jlayton@kernel.org, neilb@suse.de,
        netdev@vger.kernel.org
Subject: Re: [PATCH v8 3/3] NFSD: add rpc_status netlink support
Message-ID: <20231003110358.4a08b826@kernel.org>
In-Reply-To: <ac18892ea3f718c63f0a12e39aeaac812c081515.1694436263.git.lorenzo@kernel.org>
References: <cover.1694436263.git.lorenzo@kernel.org>
        <ac18892ea3f718c63f0a12e39aeaac812c081515.1694436263.git.lorenzo@kernel.org>
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On Mon, 11 Sep 2023 14:49:46 +0200 Lorenzo Bianconi wrote:
> +	hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
> +			  &nfsd_server_nl_family, NLM_F_MULTI,
> +			  NFSD_CMD_RPC_STATUS_GET);
> +	if (!hdr)
> +		return -ENOBUFS;

Why NLM_F_MULTI? AFAIU that means "I'm splitting one object over
multiple messages". 99% of the time the right thing to do is change 
what we consider to be "an object" rather than do F_MULTI. In theory
user space should re-constitute all the NLM_F_MULTI messages into as
single object, which none of YNL does today :(