From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-yw1-f174.google.com (mail-yw1-f174.google.com [209.85.128.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 761CA414DEC for ; Fri, 3 Jul 2026 15:43:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783093410; cv=none; b=iQ1Gjlb5epILNXICoOJ6EWGtbBl7w8OLkC7d/ps2Eg1aEDkTX5VMKGYk8kUeP9A9BU6BlEBrC2T9qfPrDYs71pEezTmI6deoGY1aDxo49Q3OT75jtE73wqPWw4uE1TSwkEfz4kb5qFKdIhLedXMM8YY2dFvSNQ9oyCXD8MWrTas= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783093410; c=relaxed/simple; bh=/aMtT2CgzoX7UI2jViPbwCEZh995kH6Bd0vInKP2ZLg=; h=Date:From:To:Cc:Message-ID:In-Reply-To:References:Subject: Mime-Version:Content-Type; b=EV/HxjqBGXm5CtyDrtCHQYhp433Uo8N+cvkgb6nOuP96/76JceI0zkTvwbO5SbWID2Uoo5sOIN36nRhSqPf8Okm6FA778lNYbHGgrnEArgHzsjhOavod1jXwzq4sPHDk6iwKAIZcHFdmS92WF96OAYBrhgEB8g0qM+XzZMVr1Ik= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=V843hRpe; arc=none smtp.client-ip=209.85.128.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="V843hRpe" Received: by mail-yw1-f174.google.com with SMTP id 00721157ae682-80bb8287d99so7805957b3.1 for ; Fri, 03 Jul 2026 08:43:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1783093407; x=1783698207; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=/aMtT2CgzoX7UI2jViPbwCEZh995kH6Bd0vInKP2ZLg=; b=V843hRpedUQzRMHE+ChxlEVQksb8qkgcSrBdJYy2FPXRlFU979ILjJLNUi6JgrLYVB a19hjhB4mOGB6wCxc8gwS3D9jM3M2f16D+su8TdL5L3tbQtZEVTeim0R0PuRwFy2/8QN yXkhl8ZhsbSL57KuIC0Zyau1wxC37wCMAs71XQcNeB5n2CIpXjlUBvi4JMgfP9Ly6kUm CT/q6oLzCtchD4PUG6puYFS3dpGswsj06YJ3bB2Og/nqvPEpbmqKoOfTxKncS5CXsxe9 P3DTkCZyINJSWPJx/fyJdqXI3OXCDK7OXHd5nnY2FJtNMyHTazVXKg8Pzyo+ca4caa2m 2TvA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1783093407; x=1783698207; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:x-gm-gg:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=/aMtT2CgzoX7UI2jViPbwCEZh995kH6Bd0vInKP2ZLg=; b=PG5Ecy/KCR1p+CEHJTgqPFN90ZMAGyF/Nu/7jU5I23yLivKeMr+VGTXyBrnE/JWx38 m96J7DvDKWmwrz2Q9rgJIrcQ3Qm8aFVzIsm5uR5Da8kg7jXVQuwNZzhnVUD9Fpyu2YsE qooe/x52tiBAcwIU/W4PHIyowX0YnRuoLCQcK9BOVWAISNfMoMnVFBii69aHhgJVcKen HDOyomN0FAxxRXjbucJLidOUGE9/iWTeSgX5Sw37vp9kxxfA/c3TSo58WnoZBlNvpCX9 hK7dVstZZkGtEQXrtTNYbKLHuWEfr8o4IKiiyTQB67OZ8DJF7Op1vD5dgDTrsm6XG2dC EZkg== X-Forwarded-Encrypted: i=1; AHgh+RrJMly5eGv0c1fc4DuIdZxzmWGE0G2F87DfDumO1T5NzptKAIXeyWLGzbzZBTJDaLL6xIXY9CY=@vger.kernel.org X-Gm-Message-State: AOJu0YxJBTaDp7X+XVpNQM0ZTKkMHG3M0xTlkXO/vf0RHCgKzoeIeDWt pLRj6UjVSFqNOe1MBirC4Cc037C5Oz2yRAPE5UZC6OxDXa5yUJQyRQdKDPy0AQ== X-Gm-Gg: AfdE7ckb2HM9nOYBR2uHaWnMQpz4EjdG3d4cCi3N4xBITatEAWsdQffehbZZZi4w0nS plp8zhH/FqKM3V501ibcq1r5Vfvmgu5Zxi7WPHx55qqw17YQpJqwKYm3SGH4uDJ3p06I1ObnOVc VTmxulHNreVkgfRTYA1QJ6rUkW+hsv57m931ybSstTk+aiHeK5liWhtnh2O2WMbdU47pCkpitpF KCep+AzmhNfqzHEr2ViuIIDPZpXMlS4cGQVYGJQrysE0dgYgQvhArswuCkty5Ldj+KHYs0/ToPV 1lWd7qmWr6sPC3rkGkNYwWCmu/jCmDQ2NgU8ea3MPIhdG8i6D8uXwPVr3zA1JH0/z2cYQsSXgU5 RCl393/TRHDqSTFxOx/zo1PPatLlGx9/zbDVeo4gdiG/EqDzllToy3b+157goCXF/moLzrUQq6Z +9jko3IJj+I9GCmdlXzc+h4uDd1mp1ePExIsGJldZSWz/+ik1rXQCmcJnku3ox8vfH3w== X-Received: by 2002:a05:690c:6712:b0:80d:7292:6142 with SMTP id 00721157ae682-8171ecd4c7fmr2645837b3.27.1783093407202; Fri, 03 Jul 2026 08:43:27 -0700 (PDT) Received: from gmail.com (172.235.85.34.bc.googleusercontent.com. [34.85.235.172]) by smtp.gmail.com with ESMTPSA id 00721157ae682-8144b049939sm25358117b3.32.2026.07.03.08.43.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Jul 2026 08:43:26 -0700 (PDT) Date: Fri, 03 Jul 2026 11:43:26 -0400 From: Willem de Bruijn To: Kuniyuki Iwashima , Eric Dumazet Cc: "David S . Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , Andrew Lunn , netdev@vger.kernel.org, eric.dumazet@gmail.com Message-ID: In-Reply-To: References: <20260701125112.3652880-1-edumazet@google.com> Subject: Re: [PATCH net-next] tun: no longer rely on RTNL in tun_fill_info() Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Kuniyuki Iwashima wrote: > On Wed, Jul 1, 2026 at 5:51=E2=80=AFAM Eric Dumazet wrote: > > > > Update tun_fill_info() to read device configuration fields (flags, ow= ner, > > group, numqueues, numdisabled) locklessly using READ_ONCE(). > > > > Annotate all writes to these fields in the control paths with WRITE_O= NCE() > > to prevent data races, as these fields can be modified concurrently v= ia > > ioctls (TUNSETPERSIST, TUNSETOWNER, TUNSETGROUP, TUNSETIFF) or queue > > attaching/detaching. > > > > Signed-off-by: Eric Dumazet > = > Reviewed-by: Kuniyuki Iwashima Reviewed-by: Willem de Bruijn