From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794380095; b=a7uQrhM2GxfeBPje+GjSG/loYoEve8IZTDirDg0ZZN9vQxS1uBluyZFucLsUDKDvBEd0 9WPbOfaE8iIXe4gxvk3KrTSa8UHr+IiubXg68vwpbCp87juOWa9eDccxVZoWohge4jGU7 338cvY3JtWpEaL+EVzwfLFf8z3QH9KywH1eC3UXUuTfAg4Gre26u2itm1kpMPR1HPgasR C0VZ5fNbZU/fcsfZtR+OpMOqRIPodzfiiZzs5QsiO7u8Gsn7oY6vdSCxiv0fcycd1rR8f dWvkWpjjGUTvqAXBF19/YItFR+JRATk0K4oSMDv2kf7EbiFUGV2q0lMgj9A8eFG5c9g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794380095; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=GHgqJYrYhwfpJ2s4cOv9IoeBIrtVH/Rn+VN0bzcAnl0=; b=p7uFAI2fXD4NiAMPDqZ2zSwnLtNErB3Vr5qnN02/o92unbt31eQBWtWQQxCwDfXwGocS 1bO09SQgQ9qI5JFYQxXofEPDK87n7a323N0TDwC18Bvf5p81h9u11Gogqb5UwP0voYdM4 1Mc6FExm6/CelJMWDSqinDeGYy5nMpLHxyWieQ8O1YWC6iusESjMrGo9Ew4hGyjiTyDsy bTcf11AyqNXSDnS/WQu/6TxPnRfGxIVXUqB8Cc7nBkwINUUSWO5Gvv/8i/8dx0LxNYqAZ NQ8xM+5R7ir29ltXLGN0AkAqXoggJfhAFzrASBDyJR0X+sgF4IQLO4glyANb1nlu4Zg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="oN/kAa+o"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2D290606A31C for ; Wed, 11 Nov 2026 06:54:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=oN/kAa+o Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3CD7E1F00A05; Wed, 11 Nov 2026 06:54:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794380094; bh=GHgqJYrYhwfpJ2s4cOv9IoeBIrtVH/Rn+VN0bzcAnl0=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=oN/kAa+oQ9IVl9T+R+XDFEtsHajUoCowFhM7iYR6nwlKTxjKEWscu1F5PrhxXJ8+d Xs/ny+fHC09ZbeDsiaz5Jg71gc0ttroroqrEHK61xtvOOpiZ3ASpfhi1alNuAOlqAO OsJ3b/uojECvsnZXNCT01FzPy9T/U/Xu1+NiZfabbIrRM1Hs2fKuV8I/fUurnJQlWI 8kAItmt0AftTn1iWIqrRoanhDSGI36m+MZyk6xb5SKxq14ZIG3j/J/ejHT9rQ51lVY QaAebyTgEkxvZXFv0OXQZKEZ4/2KLaj/3kynRg9ZK++ZKiKCgUDv6ipHAn6T9JxCDp oSX1v0zHKXgNg== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH] tty: pty: mark lockless flow control snapshots Reply-To: sashiko-reviews@lists.linux.dev To: "Zhu Jun" Cc: linux-serial@vger.kernel.org In-Reply-To: <20261111064744.17235-1-zhujun2@cmss.chinamobile.com> References: <20261111064744.17235-1-zhujun2@cmss.chinamobile.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 11 Nov 2026 06:54:53 +0000 X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > The PTY write and write-room callbacks inspect flow.stopped without > flow.lock, while TCXONC updates it under that lock. KCSAN reports the > write-room check racing with __stop_tty(). >=20 > These callbacks take a snapshot of flow control: the state can change > again before a write, and the flip-buffer operations provide their own > serialization. Use data_race(READ_ONCE()) for both checks to document the > intentional race and ensure each check uses a single load. >=20 > Fixes: 1da177e4c3f41 ("Linux-2.6.12-rc2") > Signed-off-by: Zhu Jun Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261111064744.1723= 5-1-zhujun2@cmss.chinamobile.com?part=3D1