From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B433C10F92EB for ; Tue, 31 Mar 2026 18:58:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=mWvXLhx+pdMLFOwah1XGFke1XnLglDcoMHtDAcoUZrY=; b=pNr9kklF6PMpzZ Q3PKSRTmJl7+q9QpfaWJgx0Q4yPjowa3a+hurlGsyqbcSMLxFLT4uoCZnsKZhm8jbAK4ZOjZU/0EK DU4ZdI5l0877NXzZtRfyyYmGSCTp3/PtFi/kgMkLmbCCw04HwzLwqb8hQefS5NI7k/wKinbrZZl8B mqN7iVFesX9AJga9x6B19/5UxBA3J2oK5+cQH+vC97bOd82PeTffzUQLSl+adRZAnIberIBeN+h1I jRuCF2OID0SRDO1QFOryDNwHl+uysBld/DpVhL++oBc+ua6cJUu+9VnMW/Wn/0ry/ncoqncHD3NOv jqnEsgoyIceyw4SCRi6g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1w7eIG-0000000DRSM-1SvI; Tue, 31 Mar 2026 18:58:28 +0000 Received: from mailout1.hostsharing.net ([2a01:37:1000::53df:5fcc:0]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1w7eID-0000000DRRy-21pp for linux-riscv@lists.infradead.org; Tue, 31 Mar 2026 18:58:27 +0000 Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384 client-signature ECDSA (secp384r1) client-digest SHA384) (Client CN "*.hostsharing.net", Issuer "GlobalSign GCC R6 AlphaSSL CA 2025" (verified OK)) by mailout1.hostsharing.net (Postfix) with ESMTPS id 28B51361; Tue, 31 Mar 2026 20:58:03 +0200 (CEST) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 16AC560293F2; Tue, 31 Mar 2026 20:58:03 +0200 (CEST) Date: Tue, 31 Mar 2026 20:58:03 +0200 From: Lukas Wunner To: Han Gao Cc: Bjorn Helgaas , Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= , Jonathan Cameron , Ilpo =?iso-8859-1?Q?J=E4rvinen?= , Kees Cook , Chen Wang , Manivannan Sadhasivam , linux-pci@vger.kernel.org, sophgo@lists.linux.dev, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Han Gao , Icenowy Zheng , Inochi Amaoto , Vivian Wang , Yao Zi Subject: Re: [PATCH 0/2] PCI: Allow disabling port services on broken root ports Message-ID: References: <20260331175658.1015829-1-gaohan@iscas.ac.cn> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20260331175658.1015829-1-gaohan@iscas.ac.cn> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260331_115825_667582_7C87152E X-CRM114-Status: GOOD ( 14.01 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Wed, Apr 01, 2026 at 01:56:56AM +0800, Han Gao wrote: > SG2042's PCIe root ports only support MSI, not MSI-X. The MSI > controller provides only 32 vectors shared across all devices behind > each root port. When native port services claim vectors from this > limited pool, downstream devices are starved of interrupts, resulting > in zero interrupts delivered and driver timeouts (e.g. amdgpu fence > fallback timer expired on all rings). Have you considered setting the pci_dev::no_msi flag on the Root Ports to force them to use INTx interrupts instead of MSI? That would seem like a cleaner solution. There are already several devices for which the flag is set in drivers/pci/quirks.c, see quirk_no_msi(). > Some PCIe root ports break MSI delivery to downstream devices when > native port services (AER, PME, bwctrl, etc.) are active. The existing > pcie_ports=compat kernel parameter works around this globally, but > affects all ports on the system. > > This series adds a per-device mechanism to skip port service probing: > 1. Introduce PCI_DEV_FLAGS_NO_PORT_SERVICES flag and wire it into > the PCIe port driver > 2. Apply it via quirk to Sophgo SG2042 root ports [1f1c:2042], which > fail to deliver MSI interrupts when port services are enabled I think we should try to minimize such workarounds or at least make them as non-intrusive as possible, so please try the no_msi approach instead. I also don't see why the stable designation is needed TBH. Thanks, Lukas _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv