From patchwork Tue Nov 14 13:55:49 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 13455320 X-Patchwork-Delegate: bhelgaas@google.com 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2F7BBC07CB1 for ; Tue, 14 Nov 2023 13:56:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232007AbjKNN4p (ORCPT ); Tue, 14 Nov 2023 08:56:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49490 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231889AbjKNN4j (ORCPT ); Tue, 14 Nov 2023 08:56:39 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8BD4E1BF; Tue, 14 Nov 2023 05:56:35 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1843C4167D; Tue, 14 Nov 2023 13:56:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699970193; bh=p5enpBm/h3uKua9dX8qlaS0tuKFBhLHUpM9Hd7d/DZQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=socAihQ3HhCJY6z/F1yux89ciHZ0i9NTT73CZGbk2iSRhZrNiwOchaHzlSlA4x7mL Jh4QM7ItBKDZ7uvt+YBwdLHluA4bRtiOHB9puOtJVrH5qYkAkdFSJ4RyZ4K1pqPdQk 05axIFOg4Fj8Z2e/ZPr4P3ECM6EB7jOamGMzz+83rXjq3+SB6Zot6mAiEiW0UVk+3n BmGlycYYJsSd/S+e8MeN+OvJcmpDhKFMUZOZT06+LH8LE8ekq2/TFUmBOjwoKLLcnC 7mTgPdbWtX+7/9iEi/vQXd4cG4nrCU1iz5x9Ey8dAOhYMA6IvF3upeRRZ+FJnD4xwi kmfFcMjOGmyoA== Received: from johan by xi.lan with local (Exim 4.96.2) (envelope-from ) id 1r2tu2-0008PR-2N; Tue, 14 Nov 2023 14:56:30 +0100 From: Johan Hovold To: Lorenzo Pieralisi , =?utf-8?q?Krzysztof_Wilczy?= =?utf-8?q?=C5=84ski?= , Bjorn Helgaas Cc: Andy Gross , Bjorn Andersson , Konrad Dybcio , Manivannan Sadhasivam , Rob Herring , Nirmal Patel , Jonathan Derrick , linux-arm-msm@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold , stable@vger.kernel.org, Michael Bottini , "David E . Box" Subject: [PATCH 2/6] PCI: vmd: Fix deadlock when enabling ASPM Date: Tue, 14 Nov 2023 14:55:49 +0100 Message-ID: <20231114135553.32301-3-johan+linaro@kernel.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231114135553.32301-1-johan+linaro@kernel.org> References: <20231114135553.32301-1-johan+linaro@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The vmd_pm_enable_quirk() helper is called from pci_walk_bus() during probe to enable ASPM for controllers with VMD_FEAT_BIOS_PM_QUIRK set. Since pci_walk_bus() already holds a pci_bus_sem read lock, use the new locked helper to enable link states in order to avoid a potential deadlock (e.g. in case someone takes a write lock before reacquiring the read lock). Fixes: f492edb40b54 ("PCI: vmd: Add quirk to configure PCIe ASPM and LTR") Cc: stable@vger.kernel.org # 6.3 Cc: Michael Bottini Cc: David E. Box Signed-off-by: Johan Hovold Reviewed-by: Manivannan Sadhasivam --- drivers/pci/controller/vmd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c index 94ba61fe1c44..0452cbc362ee 100644 --- a/drivers/pci/controller/vmd.c +++ b/drivers/pci/controller/vmd.c @@ -751,7 +751,7 @@ static int vmd_pm_enable_quirk(struct pci_dev *pdev, void *userdata) if (!(features & VMD_FEAT_BIOS_PM_QUIRK)) return 0; - pci_enable_link_state(pdev, PCIE_LINK_STATE_ALL); + pci_enable_link_state_locked(pdev, PCIE_LINK_STATE_ALL); pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_LTR); if (!pos)