From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) (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 96684223DFF; Tue, 25 Aug 2026 20:32:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.7 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787689938; cv=none; b=M92JiFo+ynRVT+fMsIQRCUsTzBfDRkdm3M7rMT7VanW8O4nId7nJLV4WqQ1ypVL7ipgQZasUMIC4qzLIGcFn0XuYsRU075j4fhsmu7Jk/ZoUSVVXeJ0+7ntU9h3hsjBeBTrYmWNaaD5ZcC9c4Spn9mhMu9SsqEm6eZUtGFSrlr8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787689938; c=relaxed/simple; bh=zInRDHH5JXAV2MYOFMLW0uweBzSOuIh0YeeaHf9J/m4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=LpRnkt/gJ9jz0L2eTB2Cf+I0NPEt8HgHmSfx1/QnUCjZNQTWmnBsQs695MKTCTSthq/1iZcIBWhFvMvNj4r5G/rIB+7VjcfK2Gj8MgmARV8TBKhlHytSlQ1Sw0UD1y4wAfurwGjuse6LtTYJ7jBFylfcKZ5H8iWK34WOMlfH/4k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=k2gi6As2; arc=none smtp.client-ip=192.198.163.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="k2gi6As2" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1787689936; x=1819225936; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=zInRDHH5JXAV2MYOFMLW0uweBzSOuIh0YeeaHf9J/m4=; b=k2gi6As2mkN5cMGd2upib0Ri+t//2fG6lbhbD77/yk5qT0hgNrWC4wEh PslXPppTEsltxfzeh+l4BZ09Ycq1H18csQxqUKIqVj426GYBF2kZ7r1Pd zbJS+L4H7IguL2WeWUh3o9mi/iRkZKXQEZoRshCXc2eQx8NJTxFQUDUkJ 4VwwypLQfGmhctDX+mHX7Ls06ohCXT58iGqpM7Cgi0qcgFsvFVsi/Pct1 RjU9C+SlK53oKVXwoli0uA6ficegJWHaAOs7g67+ZEMg0rEJ1XNG9tuhk ZDVj1QnnmoHhz0ts6h0g9QaM13aGozS6FZ6NOi0u2GgdkxyPsE+pcYSt+ A==; X-CSE-ConnectionGUID: V7dWd6rfQQCAoNl2fBtTtw== X-CSE-MsgGUID: uMssCjYkQ9W/MD0h344g7g== X-IronPort-AV: E=McAfee;i="6800,10657,11886"; a="113703170" X-IronPort-AV: E=Sophos;i="6.25,243,1779174000"; d="scan'208";a="113703170" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Aug 2026 13:32:15 -0700 X-CSE-ConnectionGUID: bEihwMWuQaKmNCQoISzhxQ== X-CSE-MsgGUID: fbvABTmQQ5qtj/jzR5ZsRA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,243,1779174000"; d="scan'208";a="271177728" Received: from rchatre-mobl4.amr.corp.intel.com (HELO [10.125.109.2]) ([10.125.109.2]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Aug 2026 13:32:14 -0700 Message-ID: <05b84967-fe76-4a69-9b36-ae958946e244@intel.com> Date: Tue, 25 Aug 2026 13:32:12 -0700 Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v10 08/12] cxl: Reject CXL Reset on multifunction devices To: Srirangan Madhavan , Alison Schofield , Bjorn Helgaas , Davidlohr Bueso , Ira Weiny , Jonathan Cameron , Vishal Verma , linux-cxl@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Alex Williamson , vsethi@nvidia.com, alwilliamson@nvidia.com, Sai Yashwanth Reddy Kancherla , Vishal Aslot , Manish Honap , Jiandi An , Richard Cheng , linux-tegra@vger.kernel.org References: <20260804192958.1823952-1-smadhavan@nvidia.com> <20260804192958.1823952-9-smadhavan@nvidia.com> From: Dave Jiang Content-Language: en-US In-Reply-To: <20260804192958.1823952-9-smadhavan@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/4/26 12:29 PM, Srirangan Madhavan wrote: > CXL Reset can be exposed as a PCI function reset method only when the > reset is function-scoped. PCI reset-method probing runs during > enumeration, so walking sibling functions there can race with functions > that have not been added to the bus yet. > > Reject multifunction devices for now instead of trying to infer reset > scope from sibling state. Systems that can prove a multifunction device > has function-scoped CXL Reset can be enabled later. > > Signed-off-by: Srirangan Madhavan Reviewed-by: Dave Jiang > --- > drivers/cxl/core/resource.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/cxl/core/resource.c b/drivers/cxl/core/resource.c > index 6d4528f77c53..464ca9bdae05 100644 > --- a/drivers/cxl/core/resource.c > +++ b/drivers/cxl/core/resource.c > @@ -979,6 +979,9 @@ int cxl_reset_function(struct pci_dev *pdev, bool probe) > if (dvsec < 0) > return dvsec; > > + if (pdev->multifunction) > + return -ENOTTY; > + > if (probe) > return 0; >