From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9A79132D7D9 for ; Thu, 19 Feb 2026 10:36:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771497408; cv=none; b=lN0U9FNp0/t7NuWXm7FIegLNQgZDPgllieic4mJ3N0/AWKL9bx+HzVyc3E7munRXcAJCHj7cfItqYvmhMCAcdWkqBx6DlTFz5velk7WNbPKyDHVTQjS6D1g+LRN6L2Ej2Awi4khYmyNgn6vvvUeSDQ9UFPZKTfTCn9VXpl4OE5U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771497408; c=relaxed/simple; bh=oqw0KlNKIPYnEI20309wgxqKSge7eobGKUbr1LdjuGY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PaOq9/Ik/TLD1f769v+8UFLzUmMC2Z5tfpHyvc9Vh2I0Wc/fYwAe31eZdvmXDBA9eyY8X1cBnK0eEwjILVUIfKvm7Im3XBiW7UedRIzuI1gpDGB7vfDHOWJJAatEGqRt+Ez+0qMg/UuHWVJ3gN63G31IStjqInIeh6P+0sAJcsI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=IMvTI7vh; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b=qIsEgonr; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="IMvTI7vh"; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b="qIsEgonr" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1771497406; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=0HuCXThfRUEeEl7yH4RijL3+g7m+evVIDET2wFtyGPA=; b=IMvTI7vhk3vuRkMM2kkV41ium5VGv7PT9IoyOLKQfO/Eu8PZ5TdwKuDhseOAlr5k5vvo12 b1/S3HPV55lD4FePO7TyemdOfj4e8w2Y1lh3/O1oE2Zxw0PoCyKtTEzgcH7w49ej97W6oF WOjlcHbTBcQNG0DsJ2XQeW5Kr6iENdE= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-683-vgXo3jsKOjWQDDbDaNp6Pg-1; Thu, 19 Feb 2026 05:36:45 -0500 X-MC-Unique: vgXo3jsKOjWQDDbDaNp6Pg-1 X-Mimecast-MFC-AGG-ID: vgXo3jsKOjWQDDbDaNp6Pg_1771497404 Received: by mail-wm1-f70.google.com with SMTP id 5b1f17b1804b1-48378df3469so8101705e9.1 for ; Thu, 19 Feb 2026 02:36:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=google; t=1771497404; x=1772102204; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=0HuCXThfRUEeEl7yH4RijL3+g7m+evVIDET2wFtyGPA=; b=qIsEgonrPfvZJWqC1SF7flDp7dYt/nEHIjpY99Jbl9Yo4ZoBYfcrfBxW98RFMYJStX OhWdWkrrmR7WZe1IoL+EnvtqZyDTl5catuoBvtFPloxY/FDnMEW4aySa9FLP3I+23f6w AQVPSUQZcFHfTcJurL3NXkg5ArIZZt22k7TQ/WeBEreojzEvkvBTguymSNbQOBciACG0 IuVknXHwPhcfjTQegTSKy6f7mp3eMYtKk2puiPpfKWRr1jhAdat/JTLt+3zgvTlsH9vs uw9UGWpTEBDOLfX/KaVNCH9rWBOuI6o22LJpmnBKjXJoBwHlfuO0lzW/fF0yksVGrL+L P/gQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1771497404; x=1772102204; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=0HuCXThfRUEeEl7yH4RijL3+g7m+evVIDET2wFtyGPA=; b=dDGiqM3H1dI4/Uuf45KjM6iGZLGtvX611CFoTXHiqm5dwf/mBC8JpqVhk2XraPb7aU egkDjYd6jCwHc1OuDhVSG6MhorZwi83ctp+T77fKy2H0MuBMVdFn5xOcdyLyqfBwzi9N wecuyLvJJmCSSk7esAvV4dS8FuBAEEni1IdI/9D6ZK4HMpfKHWeNxLhZiN2u9/99ScAU KOSjMqXicWN92fZOMFFNzE1/cyUvqNtRNKU/QA5Di7K+sLkwhH4fPTXUYx/ZF2aYJ/3M NnFxR3+ajDrUImsdt9lBAHwwFDhi+KsYmjXJDLbBqZv6efDNYDM5ATAdLx7oWwQhnYLu 2vBQ== X-Forwarded-Encrypted: i=1; AJvYcCWioL8a4R+xewh7sQ/EcJLfsh5d+x9CgYmI/n1/LXT51kvVjqTiKDG24/9h+WSRV142XEvWSc1JEPQF3zY=@vger.kernel.org X-Gm-Message-State: AOJu0Ywyhvj7FsKmejTOhUVqkyL+3C/kHUf3Zis0Y2cm/kNfA3OZAkGG 8wymi1J8AraOeG0o1vo60qwBQBl8em2GGuB3QbevtsDqVeyoimoUNT5ObVCDUen7FujcbNNd+hi ZgQFVPhYWNIcJtBnQcbS23cK/Aq+eNfucCdP32FbS6BKxNvvloZHPW98tRrPqVgXcFw== X-Gm-Gg: AZuq6aKxjkpOoH6/ZrKWjUEhv/mFMn/agY/q4PZ3Qn778kUT/UKOWjNzdGeOJhG5w/p Ps7hhVllMD850N3V2wDd3WswUQFwWcePe7Ydn5s70TV4TNXpU8BqssOLnjYIab8Cu8pnnGd20GO amw6Y7CL8WH3rIMfSFtw7EWm0D8E7Dj1Jrrd9zIdlC+Hn+ShfgV8OepfN/otNTmF/Roy7cFl1VJ aUcPqpABRRnkzmM+Bz/cdnG56BdawnXuf4FJAeAv+4IcwYRa1ujORB9UR99pZ7OQ+zyL3lEqCJc io3xaaXZJ4Ffsby24Do1GjlHuck7PJAL+8nKt0QOWmshiXeWbQfGpZI20gq0H4ggJNucJpGqHOJ I2KG+/xnZCWlkCh80eufUnOYwaDUKmCLLwtFv2ImHlcWAcEh6cTf5fQZAVX3uRKsXhY/ZM9M= X-Received: by 2002:a05:600c:214b:b0:47e:e051:79ee with SMTP id 5b1f17b1804b1-4839fe90522mr18467645e9.3.1771497403800; Thu, 19 Feb 2026 02:36:43 -0800 (PST) X-Received: by 2002:a05:600c:214b:b0:47e:e051:79ee with SMTP id 5b1f17b1804b1-4839fe90522mr18467255e9.3.1771497403315; Thu, 19 Feb 2026 02:36:43 -0800 (PST) Received: from sgarzare-redhat (host-82-53-134-58.retail.telecomitalia.it. [82.53.134.58]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4839f99067dsm17354955e9.29.2026.02.19.02.36.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 19 Feb 2026 02:36:42 -0800 (PST) Date: Thu, 19 Feb 2026 11:36:40 +0100 From: Stefano Garzarella To: Bobby Eshleman Cc: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Stefan Hajnoczi , Shuah Khan , Bobby Eshleman , "Michael S. Tsirkin" , Jonathan Corbet , Shuah Khan , virtualization@lists.linux.dev, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [PATCH net v2 3/3] vsock: document write-once behavior of the child_ns_mode sysctl Message-ID: References: <20260218-vsock-ns-write-once-v2-0-19e4c50d509a@meta.com> <20260218-vsock-ns-write-once-v2-3-19e4c50d509a@meta.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20260218-vsock-ns-write-once-v2-3-19e4c50d509a@meta.com> On Wed, Feb 18, 2026 at 10:10:38AM -0800, Bobby Eshleman wrote: >From: Bobby Eshleman > >Update the vsock child_ns_mode documentation to include the new the nit: s/the new the/the new >write-once semantics of setting child_ns_mode. The semantics are >implemented in a different patch in this series. s/different/preceding ? IMO this can be squashed with the previous patch, but not sure netdev policy about that. Not a strong opinion, it's fine also in this way. > >Signed-off-by: Bobby Eshleman >--- > Documentation/admin-guide/sysctl/net.rst | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) > >diff --git a/Documentation/admin-guide/sysctl/net.rst b/Documentation/admin-guide/sysctl/net.rst >index c10530624f1e..976a176fb451 100644 >--- a/Documentation/admin-guide/sysctl/net.rst >+++ b/Documentation/admin-guide/sysctl/net.rst >@@ -581,9 +581,9 @@ The init_net mode is always ``global``. > child_ns_mode > ------------- > >-Controls what mode newly created child namespaces will inherit. At namespace >-creation, ``ns_mode`` is inherited from the parent's ``child_ns_mode``. The >-initial value matches the namespace's own ``ns_mode``. >+Write-once. Controls what mode newly created child namespaces will inherit. At >+namespace creation, ``ns_mode`` is inherited from the parent's >+``child_ns_mode``. The initial value matches the namespace's own ``ns_mode``. > > Values: > >@@ -594,6 +594,10 @@ Values: > their sockets will only be able to connect within their own > namespace. > >+``child_ns_mode`` can only be written once per namespace. Writing the same >+value that is already set succeeds. Writing a different value after the first >+write returns ``-EBUSY``. nit: instead of saying that it can only be written once, we could say that the first write locks the value, to be closer to the actual behavior, something like this: The first write to ``child_ns_mode`` locks its value. Subsequent writes of the same value succeed, but writing a different value returns ``-EBUSY``. Thanks, Stefano >+ > Changing ``child_ns_mode`` only affects namespaces created after the change; > it does not modify the current namespace or any existing children. > > >-- >2.47.3 >