From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.13]) (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 12F6B244186; Thu, 4 Dec 2025 10:11:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764843083; cv=none; b=Ydy1yOmEEAUtpgBmYUmQQ8pO4Ko8GHSp7v4/H/rKPpALnoGk1cDjTyH0BzyCRae7Wd3ZbbqN+Ez7bDAbuQNWEcYXLnJ9ihpHh6BRxqkNVb2QMHzTphixa0DSNA2RyT2ADvhMrvKgxHSs8lkyNmDbU+PKc1eqQl5r1uxIW1d7NSw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764843083; c=relaxed/simple; bh=HKfSXscOpvUdtKiz7s9Xq7/VXzagI9+7jmqmEYd8d9A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Vd+KP3+YVJx77je1pAKbJ57oXzlBRxili/SRdEYc9QV9QwiBrVZkLY2eIL3yY+yU0jGY0MJA+vKLDu/PoKP4W95fhgoH1y/ZHNt3u+rL/qnvvf7FJKxiuv/bYucYkDCXoY7VHe3QdGYviJslUscB7sbAhtumlBXItX4jrG9aZAo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=Jk1njphi; arc=none smtp.client-ip=198.175.65.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="Jk1njphi" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1764843081; x=1796379081; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=HKfSXscOpvUdtKiz7s9Xq7/VXzagI9+7jmqmEYd8d9A=; b=Jk1njphiKkwbhLojGSFlQeHTRgQhJ39ItxWK75xPglFR84fQNSM504wP Bt6YiwcJEqZZ26cJEa4kJ39JaRKQsP3YQzB8KzBTHT2RdHgYON3D9TK23 2grLvAglBRepptNgz/xpLKZD1qy/bepsCKEWK0muo6knTknwGgmNGLtgD 188u/tYXs7ameta00CV6Z+ZjU9DgjlD8sC2+JRhoGXbAX+431fdU0NC9d y2IKJhJd27fLXG6HluAN1pZXTRfDEhuwSaJ8ZzF77L27Yz3psEqskGwhh L9GndJXiF9zb8HwHq8TcOGNUv6cYvF2S7G79a/dmRQnO9yEgyXscos1D9 A==; X-CSE-ConnectionGUID: Jpc0sr/jR8eH9bkKFDQ7ig== X-CSE-MsgGUID: mgXdaJi7RmWoaqJsCTbbvg== X-IronPort-AV: E=McAfee;i="6800,10657,11631"; a="77965781" X-IronPort-AV: E=Sophos;i="6.20,248,1758610800"; d="scan'208";a="77965781" Received: from orviesa010.jf.intel.com ([10.64.159.150]) by orvoesa105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Dec 2025 02:11:20 -0800 X-CSE-ConnectionGUID: ZJCJnOYbTRibjJBbOJRvKw== X-CSE-MsgGUID: mYsb8kqaSCm0Rm7Ep/T/ZQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.20,248,1758610800"; d="scan'208";a="194222247" Received: from black.igk.intel.com ([10.91.253.5]) by orviesa010.jf.intel.com with ESMTP; 04 Dec 2025 02:11:18 -0800 Received: by black.igk.intel.com (Postfix, from userid 1001) id E79EBA9; Thu, 04 Dec 2025 11:11:16 +0100 (CET) Date: Thu, 4 Dec 2025 11:11:16 +0100 From: Mika Westerberg To: Haotian Zhang Cc: andreas.noever@gmail.com, westeri@kernel.org, YehezkelShB@gmail.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] thunderbolt: Return -ENOTSUPP when cm_ops callbacks are missing Message-ID: <20251204101116.GA1613537@black.igk.intel.com> References: <20251204093224.1431-1-vulab@iscas.ac.cn> 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=utf-8 Content-Disposition: inline In-Reply-To: <20251204093224.1431-1-vulab@iscas.ac.cn> Hi, On Thu, Dec 04, 2025 at 05:32:24PM +0800, Haotian Zhang wrote: > Several tb_domain* helpers return -EPERM when the corresponding cm_ops > callback is NULL. A NULL callback indicates the operation is not > supported by the connection manager, not a permission denial. These specifically return -EPERM on purpose because these are used when PCIe tunnel is established and torn down. If the connection manager implementation does not provide them it means you don't have permission to deal with the PCIe tunnels.