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{ "id": 2218230, "url": "http://patchwork.ozlabs.org/api/covers/2218230/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pci/cover/20260331175658.1015829-1-gaohan@iscas.ac.cn/", "project": { "id": 28, "url": "http://patchwork.ozlabs.org/api/projects/28/?format=api", "name": "Linux PCI development", "link_name": "linux-pci", "list_id": "linux-pci.vger.kernel.org", "list_email": "linux-pci@vger.kernel.org", "web_url": null, "scm_url": null, "webscm_url": null, "list_archive_url": "", "list_archive_url_format": "", "commit_url_format": "" }, "msgid": "<20260331175658.1015829-1-gaohan@iscas.ac.cn>", "list_archive_url": null, "date": "2026-03-31T17:56:56", "name": "[0/2] PCI: Allow disabling port services on broken root ports", "submitter": { "id": 92681, "url": "http://patchwork.ozlabs.org/api/people/92681/?format=api", "name": "Han Gao", "email": "gaohan@iscas.ac.cn" }, "mbox": "http://patchwork.ozlabs.org/project/linux-pci/cover/20260331175658.1015829-1-gaohan@iscas.ac.cn/mbox/", "series": [ { "id": 498236, "url": "http://patchwork.ozlabs.org/api/series/498236/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pci/list/?series=498236", "date": "2026-03-31T17:56:58", "name": "PCI: Allow disabling port services on broken root ports", "version": 1, "mbox": "http://patchwork.ozlabs.org/series/498236/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/covers/2218230/comments/", "headers": { "Return-Path": "\n <linux-pci+bounces-51601-incoming=patchwork.ozlabs.org@vger.kernel.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "linux-pci@vger.kernel.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c04:e001:36c::12fc:5321; helo=tor.lore.kernel.org;\n envelope-from=linux-pci+bounces-51601-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)", "smtp.subspace.kernel.org;\n arc=none smtp.client-ip=159.226.251.21", "smtp.subspace.kernel.org;\n dmarc=none (p=none dis=none) header.from=iscas.ac.cn", "smtp.subspace.kernel.org;\n spf=pass smtp.mailfrom=iscas.ac.cn" ], "Received": [ "from tor.lore.kernel.org (tor.lore.kernel.org\n [IPv6:2600:3c04:e001:36c::12fc:5321])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4flbcG4NNwz1y1q\n\tfor <incoming@patchwork.ozlabs.org>; Wed, 01 Apr 2026 05:04:46 +1100 (AEDT)", "from smtp.subspace.kernel.org (conduit.subspace.kernel.org\n [100.90.174.1])\n\tby tor.lore.kernel.org (Postfix) with ESMTP id EBF043040000\n\tfor <incoming@patchwork.ozlabs.org>; Tue, 31 Mar 2026 17:57:20 +0000 (UTC)", "from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id E48F4345CBE;\n\tTue, 31 Mar 2026 17:57:19 +0000 (UTC)", "from cstnet.cn (smtp21.cstnet.cn [159.226.251.21])\n\t(using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby smtp.subspace.kernel.org (Postfix) with ESMTPS id 413D4391833;\n\tTue, 31 Mar 2026 17:57:16 +0000 (UTC)", "from localhost.localdomain (unknown [223.166.95.230])\n\tby APP-01 (Coremail) with SMTP id qwCowABH8GvrCsxpCP3GCw--.20050S2;\n\tWed, 01 Apr 2026 01:57:00 +0800 (CST)" ], "ARC-Seal": "i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1774979839; cv=none;\n b=UUJTfGkoRsYzFn1Yv/Lg+0ncpES09ndAlZLM0NfRlOqCH4tz0GZaBpFiiySarbI+HrqMaw0RaioaptWLqVniJeP3Rt1SHjcjYfmA465RaWGp8CvAaVWXGA89ZDMdTPOah/ZKr03ew84xkYxS9QCB6tJl60ACdNu4yFjyxnsMwLM=", "ARC-Message-Signature": "i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1774979839; c=relaxed/simple;\n\tbh=zOv/9RphY8o5rG3kxKtLeEGTPsN0fRlOfNUMTN4h4F8=;\n\th=From:To:Cc:Subject:Date:Message-ID:MIME-Version;\n b=CJVnieENr//zpkTjfTZcX6Zl5/odeJW5GUXHkHx2PHRrL6HLQPayBjFhHGHNH/VbZCsIIQiMbkJyo9+2p34XdH9MUddsymqDrxoS+B1VzvIfoTKbgmvzbeHYky8r067sVYRalTP6CAc4pHeuSOnmz1IvbAuOD1LiLo7kXj91P08=", "ARC-Authentication-Results": "i=1; smtp.subspace.kernel.org;\n dmarc=none (p=none dis=none) header.from=iscas.ac.cn;\n spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.21", "From": "Han Gao <gaohan@iscas.ac.cn>", "To": "Bjorn Helgaas <bhelgaas@google.com>,\n =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= <u.kleine-koenig@baylibre.com>,\n Jonathan Cameron <jonathan.cameron@huawei.com>,\n Lukas Wunner <lukas@wunner.de>,\n =?utf-8?q?Ilpo_J=C3=A4rvinen?= <ilpo.jarvinen@linux.intel.com>,\n Kees Cook <kees@kernel.org>, Han Gao <gaohan@iscas.ac.cn>,\n Chen Wang <unicorn_wang@outlook.com>, Manivannan Sadhasivam <mani@kernel.org>", "Cc": "linux-pci@vger.kernel.org,\n\tsophgo@lists.linux.dev,\n\tlinux-kernel@vger.kernel.org,\n\tlinux-riscv@lists.infradead.org,\n\tHan Gao <rabenda.cn@gmail.com>,\n\tIcenowy Zheng <zhengxingda@iscas.ac.cn>,\n\tInochi Amaoto <inochiama@gmail.com>,\n\tVivian Wang <wangruikang@iscas.ac.cn>,\n\tYao Zi <me@ziyao.cc>", "Subject": "[PATCH 0/2] PCI: Allow disabling port services on broken root ports", "Date": "Wed, 1 Apr 2026 01:56:56 +0800", "Message-ID": "<20260331175658.1015829-1-gaohan@iscas.ac.cn>", "X-Mailer": "git-send-email 2.47.3", "Precedence": "bulk", "X-Mailing-List": "linux-pci@vger.kernel.org", "List-Id": "<linux-pci.vger.kernel.org>", "List-Subscribe": "<mailto:linux-pci+subscribe@vger.kernel.org>", "List-Unsubscribe": "<mailto:linux-pci+unsubscribe@vger.kernel.org>", "MIME-Version": "1.0", "Content-Transfer-Encoding": "8bit", "X-CM-TRANSID": "qwCowABH8GvrCsxpCP3GCw--.20050S2", "X-Coremail-Antispam": "1UD129KBjvJXoW7JryxXF1ktFykZF18tF4DCFg_yoW8JryfpF\n\tWrWF9YyrWfKryUKwsrX3WUCFy3WF4kAryrC34DGw47urW3AryrXF9rtF93tFsrGr4xAa4Y\n\tvr95C3W5uFyDZFJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2\n\t9KBjDU0xBIdaVrnRJUUU9214x267AKxVW5JVWrJwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0\n\trVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02\n\t1l84ACjcxK6xIIjxv20xvE14v26r1I6r4UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j\n\t6F4UM28EF7xvwVC2z280aVAFwI0_Cr0_Gr1UM28EF7xvwVC2z280aVCY1x0267AKxVW8Jr\n\t0_Cr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj\n\t6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr\n\t0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E\n\t8cxan2IY04v7MxkF7I0En4kS14v26r4a6rW5MxAIw28IcxkI7VAKI48JMxC20s026xCaFV\n\tCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWl\n\tx4CE17CEb7AF67AKxVW8ZVWrXwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r\n\t1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_\n\tJF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8Jr0_Cr1UYx\n\tBIdaVFxhVjvjDU0xZFpf9x0pRHUDLUUUUU=", "X-CM-SenderInfo": "xjdrxt3q6l2u1dvotugofq/1tbiBwkDDGnL4t55SwABss" }, "content": "Some PCIe root ports break MSI delivery to downstream devices when\nnative port services (AER, PME, bwctrl, etc.) are active. The existing\npcie_ports=compat kernel parameter works around this globally, but\naffects all ports on the system.\n\nThis series adds a per-device mechanism to skip port service probing:\n 1. Introduce PCI_DEV_FLAGS_NO_PORT_SERVICES flag and wire it into\n the PCIe port driver\n 2. Apply it via quirk to Sophgo SG2042 root ports [1f1c:2042], which\n fail to deliver MSI interrupts when port services are enabled\n\nSG2042's PCIe root ports only support MSI, not MSI-X. The MSI\ncontroller provides only 32 vectors shared across all devices behind\neach root port. When native port services claim vectors from this\nlimited pool, downstream devices are starved of interrupts, resulting\nin zero interrupts delivered and driver timeouts (e.g. amdgpu fence\nfallback timer expired on all rings).\n\nHan Gao (2):\n PCI: Add per-device flag to disable native PCIe port services\n PCI: Add quirk to disable PCIe port services on Sophgo SG2042\n\n drivers/pci/pcie/portdrv.c | 3 +++\n drivers/pci/quirks.c | 12 ++++++++++++\n include/linux/pci.h | 2 ++\n include/linux/pci_ids.h | 2 ++\n 4 files changed, 19 insertions(+)" }