From patchwork Thu Mar 4 20:55:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Aring X-Patchwork-Id: 12116789 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BBDA6C433DB for ; Thu, 4 Mar 2021 20:57:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 787D364F69 for ; Thu, 4 Mar 2021 20:57:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231623AbhCDU4z (ORCPT ); Thu, 4 Mar 2021 15:56:55 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:34114 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230413AbhCDU4v (ORCPT ); Thu, 4 Mar 2021 15:56:51 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1614891325; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=wiNB48VlHfTqbkkh69Ka2ojMNQandCOUab0VuYZf6k0=; b=AJnJHBYCDebBKvn5+5YmOCWhFBzFa6dVDEEIVTF0Mh5I069lPbz7oc2Ug+bTz0nU2U7lpF UsjkgJ2QLhSPjrwNU/g8QXNfjpIDuG7VkbyR7lZvK7tQPLEXfXfAy4MKuhIF/yxKrWzmgB 0iSzSpNEP1rAFur+y3kXy/I73pWMz6c= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-554-dE1ZLy3eN6iS3Mf2tyFAuQ-1; Thu, 04 Mar 2021 15:55:23 -0500 X-MC-Unique: dE1ZLy3eN6iS3Mf2tyFAuQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C54FA108BD06; Thu, 4 Mar 2021 20:55:22 +0000 (UTC) Received: from carbon.redhat.com (unknown [10.10.115.251]) by smtp.corp.redhat.com (Postfix) with ESMTP id B53CD5C1A1; Thu, 4 Mar 2021 20:55:21 +0000 (UTC) From: Alexander Aring To: pablo@netfilter.org Cc: fw@strlen.de, netdev@vger.kernel.org, teigland@redhat.com Subject: [PATCH] netlink.7: note not reliable if NETLINK_NO_ENOBUFS Date: Thu, 4 Mar 2021 15:55:15 -0500 Message-Id: <20210304205515.34262-1-aahringo@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch adds a note to the netlink manpage that if NETLINK_NO_ENOBUFS is set there is no additional handling to make netlink reliable. It just disables the error notification. The used word "avoid" receiving ENOBUFS errors can be interpreted that netlink tries to do some additional queue handling to avoid that such scenario occurs at all, e.g. like zerocopy which tries to avoid memory copy. However disable is not the right word here as well that in some cases ENOBUFS can be still received. This patch makes clear that there will no additional handling to put netlink in a more reliable mode. Signed-off-by: Alexander Aring --- man7/netlink.7 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/man7/netlink.7 b/man7/netlink.7 index c69bb62bf..2cb0d1a55 100644 --- a/man7/netlink.7 +++ b/man7/netlink.7 @@ -478,7 +478,7 @@ errors. .\" Author: Pablo Neira Ayuso This flag can be used by unicast and broadcast listeners to avoid receiving .B ENOBUFS -errors. +errors. Note it does not turn netlink into any kind of more reliable mode. .TP .BR NETLINK_LISTEN_ALL_NSID " (since Linux 4.2)" .\" commit 59324cf35aba5336b611074028777838a963d03b