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([2a0d:3344:5521:6b10:58fd:68f:7756:389d]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-493c6375764sm315001895e9.5.2026.07.06.02.45.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 06 Jul 2026 02:45:13 -0700 (PDT) Message-ID: Date: Mon, 6 Jul 2026 11:45:11 +0200 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net-next] tun: no longer rely on RTNL in tun_fill_info() To: Eric Dumazet , "David S . Miller" , Jakub Kicinski Cc: Simon Horman , Kuniyuki Iwashima , Andrew Lunn , netdev@vger.kernel.org, eric.dumazet@gmail.com References: <20260701125112.3652880-1-edumazet@google.com> From: Paolo Abeni Content-Language: en-US In-Reply-To: <20260701125112.3652880-1-edumazet@google.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/1/26 2:51 PM, Eric Dumazet wrote: > Update tun_fill_info() to read device configuration fields (flags, owner, > group, numqueues, numdisabled) locklessly using READ_ONCE(). > > Annotate all writes to these fields in the control paths with WRITE_ONCE() > to prevent data races, as these fields can be modified concurrently via > ioctls (TUNSETPERSIST, TUNSETOWNER, TUNSETGROUP, TUNSETIFF) or queue > attaching/detaching. Sashiko-gemini notes that: __tun_chr_ioctl() -> tun_vnet_ioctl can still update tun->flags with no annotation for TUN_VNET_LE. I'm not sure if a follow-up or a v2 is preferred. /P