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 95F78FD0048 for ; Sun, 1 Mar 2026 01:18:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=nDHB89/ZLv9fTZ/CiJFM0VRlmvDkARchLTTKn2yL8Ok=; b=JFOQscaWnM1BSrgKf7JvQcVb77 una3C8H9CvQlRH1eSa52m5CUamvQkNrBT4ExQRwv71fzqU64L/cjf3jQrMY+iIz5zjCoCcaSGXknC hX90+Q2KswyFOlwvmRtMSVxq0kRLRGgHba0yz6C14UWD5wQBz57wA71tiIpHt3DbVy1t4H5MbjWx7 lCrCypogNhUEOMjRh4vk9Rz2yQi8ebpC8OCKoCkNGBN9PLHbs5XsjDEh2fijC5n7gvn4/Sj/zCdAt 4oCgKWZQwWtUyWA5HxtXO5A5S6zkmWGMmly0wPbJYcF5CDkDY2YNwEnwA5qoetZAQqQq0AjnK+PR4 iqFPy/rw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vwVSB-0000000AStT-3VqY; Sun, 01 Mar 2026 01:18:39 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vwVS8-0000000ASrK-3uZJ; Sun, 01 Mar 2026 01:18:38 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 90FCB4046E; Sun, 1 Mar 2026 01:18:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A8A39C19425; Sun, 1 Mar 2026 01:18:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772327916; bh=gYQU72GCqOuyVxiB9B+xxvQf6BEbYMT3+GqQr+b/y8Y=; h=From:To:Cc:Subject:Date:From; b=JXOWKCNft5DOUTETrnEyE8ySRCJ0Alk3LOC339aaCvKpZAO9c0aTm/d/duOyx2vHQ HblRgbdWzT9LXqoPhpCjbDvicJ1A9pU+HEESmyS5n6oxKgbArHYD9/R/iesozl7cDy 5RT8jnRAKGQo7VOou8bl6reqNBcyucc+BdW7XXZMK1OlQhl47OeyVNz4kzify35erG APkZvj4m80QELYIkepd7BgqvBtCkv0g20AOa1/7EqOVkqUvcWklB/jrdC8qimo4awB AJruqpQpj8QhbYDT6ekC04AuxbbPIQc8iHcrAZNB2y9Bjfgnlbo0t2KZZEFeB4qEzU G0rqSQaPIa7jg== From: Sasha Levin To: stable@vger.kernel.org, cassel@kernel.org Cc: Manivannan Sadhasivam , Shawn Lin , linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org Subject: FAILED: Patch "Revert "PCI: dw-rockchip: Don't wait for link since we can detect Link Up"" failed to apply to 6.12-stable tree Date: Sat, 28 Feb 2026 20:18:34 -0500 Message-ID: <20260301011834.1672987-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 MIME-Version: 1.0 X-Patchwork-Hint: ignore X-stable: review Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260228_171837_021871_AE02BA6E X-CRM114-Status: GOOD ( 16.37 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The patch below does not apply to the 6.12-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From fc6298086bfacaa7003b0bd1da4e4f42b29f7d77 Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Mon, 22 Dec 2025 07:42:08 +0100 Subject: [PATCH] Revert "PCI: dw-rockchip: Don't wait for link since we can detect Link Up" This reverts commit ec9fd499b9c60a187ac8d6414c3c343c77d32e42. While this fake hotplugging was a nice idea, it has shown that this feature does not handle PCIe switches correctly: pci_bus 0004:43: busn_res: can not insert [bus 43-41] under [bus 42-41] (conflicts with (null) [bus 42-41]) pci_bus 0004:43: busn_res: [bus 43-41] end is updated to 43 pci_bus 0004:43: busn_res: can not insert [bus 43] under [bus 42-41] (conflicts with (null) [bus 42-41]) pci 0004:42:00.0: devices behind bridge are unusable because [bus 43] cannot be assigned for them pci_bus 0004:44: busn_res: can not insert [bus 44-41] under [bus 42-41] (conflicts with (null) [bus 42-41]) pci_bus 0004:44: busn_res: [bus 44-41] end is updated to 44 pci_bus 0004:44: busn_res: can not insert [bus 44] under [bus 42-41] (conflicts with (null) [bus 42-41]) pci 0004:42:02.0: devices behind bridge are unusable because [bus 44] cannot be assigned for them pci_bus 0004:45: busn_res: can not insert [bus 45-41] under [bus 42-41] (conflicts with (null) [bus 42-41]) pci_bus 0004:45: busn_res: [bus 45-41] end is updated to 45 pci_bus 0004:45: busn_res: can not insert [bus 45] under [bus 42-41] (conflicts with (null) [bus 42-41]) pci 0004:42:06.0: devices behind bridge are unusable because [bus 45] cannot be assigned for them pci_bus 0004:46: busn_res: can not insert [bus 46-41] under [bus 42-41] (conflicts with (null) [bus 42-41]) pci_bus 0004:46: busn_res: [bus 46-41] end is updated to 46 pci_bus 0004:46: busn_res: can not insert [bus 46] under [bus 42-41] (conflicts with (null) [bus 42-41]) pci 0004:42:0e.0: devices behind bridge are unusable because [bus 46] cannot be assigned for them pci_bus 0004:42: busn_res: [bus 42-41] end is updated to 46 pci_bus 0004:42: busn_res: can not insert [bus 42-46] under [bus 41] (conflicts with (null) [bus 41]) pci 0004:41:00.0: devices behind bridge are unusable because [bus 42-46] cannot be assigned for them pcieport 0004:40:00.0: bridge has subordinate 41 but max busn 46 During the initial scan, PCI core doesn't see the switch and since the Root Port is not hot plug capable, the secondary bus number gets assigned as the subordinate bus number. This means, the PCI core assumes that only one bus will appear behind the Root Port since the Root Port is not hot plug capable. This works perfectly fine for PCIe endpoints connected to the Root Port, since they don't extend the bus. However, if a PCIe switch is connected, then there is a problem when the downstream busses starts showing up and the PCI core doesn't extend the subordinate bus number and bridge resources after initial scan during boot. The long term plan is to migrate this driver to the upcoming pwrctrl APIs that are supposed to handle this problem elegantly. Suggested-by: Manivannan Sadhasivam Signed-off-by: Niklas Cassel Signed-off-by: Manivannan Sadhasivam Tested-by: Shawn Lin Acked-by: Shawn Lin Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20251222064207.3246632-9-cassel@kernel.org --- drivers/pci/controller/dwc/pcie-dw-rockchip.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/pci/controller/dwc/pcie-dw-rockchip.c b/drivers/pci/controller/dwc/pcie-dw-rockchip.c index 8c1c922088023..ca808d8f79753 100644 --- a/drivers/pci/controller/dwc/pcie-dw-rockchip.c +++ b/drivers/pci/controller/dwc/pcie-dw-rockchip.c @@ -601,7 +601,6 @@ static int rockchip_pcie_configure_rc(struct platform_device *pdev, pp = &rockchip->pci.pp; pp->ops = &rockchip_pcie_host_ops; - pp->use_linkup_irq = true; ret = dw_pcie_host_init(pp); if (ret) { -- 2.51.0