From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 EE7112C17A0; Tue, 26 Aug 2025 11:20:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756207224; cv=none; b=jdFapH+GMsOiNFvJCfEoyJKc59PrzgAmBj8P/CSmsFjh3Xnxm4mp48JlU1ZfPnS2SI3FHwavPGw00JVVJG75MdnjRgeLsQo1/PBrnG/9OeW79I+dLVRu1m7jJLwOQfVE6w1nSunJFwgefc/EMKhRWiMsvGAW41KqSM2mxQSlFRg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756207224; c=relaxed/simple; bh=JAZBEfSc6VkHkjKKv0HqXaFJ2z7JcOqrL3Zik8aAc8A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=JoYPLt+dNOB1Wu28O/26Mgg1R6gdHW/2wbMNhS6zOLyXKjyBfys8izqqPq+P/8Jp2pYXxnNzy/+1N5O3RpaDJ2YGOFx6fEaUxYhMv6Y3vTpUx/XIUfKTRwyC6t8CqnK+KvlECtJmmkunViXbTGRIjQP/6yXwaCeG/bsDVhb5Xb4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=FjfukGZL; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="FjfukGZL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7C1EDC4CEF1; Tue, 26 Aug 2025 11:20:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1756207223; bh=JAZBEfSc6VkHkjKKv0HqXaFJ2z7JcOqrL3Zik8aAc8A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FjfukGZLQmEw1YW5r7yWOQEytjUxSHnr5M7M2A9B5EzmCb35OZMACD1TMxpi0e5tK 9W/lPSd+iKtW2vq5f2Utchj7wHDGJ2Qc9JQSo+1NBe0efibDDlNU7xKC7Y2VRKs3LY hnNjVyRH5ovx6oxjcLU2fkIEsqwngh31cd4AX+aA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Andrew , "Maciej W. Rozycki" , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , Jiwei Sun , Bjorn Helgaas Subject: [PATCH 6.16 098/457] PCI: Fix link speed calculation on retrain failure Date: Tue, 26 Aug 2025 13:06:22 +0200 Message-ID: <20250826110939.798071836@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250826110937.289866482@linuxfoundation.org> References: <20250826110937.289866482@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiwei Sun commit 9989e0ca7462c62f93dbc62f684448aa2efb9226 upstream. When pcie_failed_link_retrain() fails to retrain, it tries to revert to the previous link speed. However it calculates that speed from the Link Control 2 register without masking out non-speed bits first. PCIE_LNKCTL2_TLS2SPEED() converts such incorrect values to PCI_SPEED_UNKNOWN (0xff), which in turn causes a WARN splat in pcie_set_target_speed(): pci 0000:00:01.1: [1022:14ed] type 01 class 0x060400 PCIe Root Port pci 0000:00:01.1: broken device, retraining non-functional downstream link at 2.5GT/s pci 0000:00:01.1: retraining failed WARNING: CPU: 1 PID: 1 at drivers/pci/pcie/bwctrl.c:168 pcie_set_target_speed RDX: 0000000000000001 RSI: 00000000000000ff RDI: ffff9acd82efa000 pcie_failed_link_retrain pci_device_add pci_scan_single_device Mask out the non-speed bits in PCIE_LNKCTL2_TLS2SPEED() and PCIE_LNKCAP_SLS2SPEED() so they don't incorrectly return PCI_SPEED_UNKNOWN. Fixes: de9a6c8d5dbf ("PCI/bwctrl: Add pcie_set_target_speed() to set PCIe Link Speed") Reported-by: Andrew Closes: https://lore.kernel.org/r/7iNzXbCGpf8yUMJZBQjLdbjPcXrEJqBxy5-bHfppz0ek-h4_-G93b1KUrm106r2VNF2FV_sSq0nENv4RsRIUGnlYZMlQr2ZD2NyB5sdj5aU=@protonmail.com/ Suggested-by: Maciej W. Rozycki Suggested-by: Ilpo Järvinen Signed-off-by: Jiwei Sun [bhelgaas: commit log, add details from https://lore.kernel.org/r/1c92ef6bcb314ee6977839b46b393282e4f52e74.1750684771.git.lukas@wunner.de] Signed-off-by: Bjorn Helgaas Reviewed-by: Ilpo Järvinen Cc: stable@vger.kernel.org # v6.13+ Link: https://patch.msgid.link/20250123055155.22648-2-sjiwei@163.com Signed-off-by: Greg Kroah-Hartman --- drivers/pci/pci.h | 32 +++++++++++++++++++------------- 1 file changed, 19 insertions(+), 13 deletions(-) --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -391,12 +391,14 @@ void pci_bus_put(struct pci_bus *bus); #define PCIE_LNKCAP_SLS2SPEED(lnkcap) \ ({ \ - ((lnkcap) == PCI_EXP_LNKCAP_SLS_64_0GB ? PCIE_SPEED_64_0GT : \ - (lnkcap) == PCI_EXP_LNKCAP_SLS_32_0GB ? PCIE_SPEED_32_0GT : \ - (lnkcap) == PCI_EXP_LNKCAP_SLS_16_0GB ? PCIE_SPEED_16_0GT : \ - (lnkcap) == PCI_EXP_LNKCAP_SLS_8_0GB ? PCIE_SPEED_8_0GT : \ - (lnkcap) == PCI_EXP_LNKCAP_SLS_5_0GB ? PCIE_SPEED_5_0GT : \ - (lnkcap) == PCI_EXP_LNKCAP_SLS_2_5GB ? PCIE_SPEED_2_5GT : \ + u32 lnkcap_sls = (lnkcap) & PCI_EXP_LNKCAP_SLS; \ + \ + (lnkcap_sls == PCI_EXP_LNKCAP_SLS_64_0GB ? PCIE_SPEED_64_0GT : \ + lnkcap_sls == PCI_EXP_LNKCAP_SLS_32_0GB ? PCIE_SPEED_32_0GT : \ + lnkcap_sls == PCI_EXP_LNKCAP_SLS_16_0GB ? PCIE_SPEED_16_0GT : \ + lnkcap_sls == PCI_EXP_LNKCAP_SLS_8_0GB ? PCIE_SPEED_8_0GT : \ + lnkcap_sls == PCI_EXP_LNKCAP_SLS_5_0GB ? PCIE_SPEED_5_0GT : \ + lnkcap_sls == PCI_EXP_LNKCAP_SLS_2_5GB ? PCIE_SPEED_2_5GT : \ PCI_SPEED_UNKNOWN); \ }) @@ -411,13 +413,17 @@ void pci_bus_put(struct pci_bus *bus); PCI_SPEED_UNKNOWN) #define PCIE_LNKCTL2_TLS2SPEED(lnkctl2) \ - ((lnkctl2) == PCI_EXP_LNKCTL2_TLS_64_0GT ? PCIE_SPEED_64_0GT : \ - (lnkctl2) == PCI_EXP_LNKCTL2_TLS_32_0GT ? PCIE_SPEED_32_0GT : \ - (lnkctl2) == PCI_EXP_LNKCTL2_TLS_16_0GT ? PCIE_SPEED_16_0GT : \ - (lnkctl2) == PCI_EXP_LNKCTL2_TLS_8_0GT ? PCIE_SPEED_8_0GT : \ - (lnkctl2) == PCI_EXP_LNKCTL2_TLS_5_0GT ? PCIE_SPEED_5_0GT : \ - (lnkctl2) == PCI_EXP_LNKCTL2_TLS_2_5GT ? PCIE_SPEED_2_5GT : \ - PCI_SPEED_UNKNOWN) +({ \ + u16 lnkctl2_tls = (lnkctl2) & PCI_EXP_LNKCTL2_TLS; \ + \ + (lnkctl2_tls == PCI_EXP_LNKCTL2_TLS_64_0GT ? PCIE_SPEED_64_0GT : \ + lnkctl2_tls == PCI_EXP_LNKCTL2_TLS_32_0GT ? PCIE_SPEED_32_0GT : \ + lnkctl2_tls == PCI_EXP_LNKCTL2_TLS_16_0GT ? PCIE_SPEED_16_0GT : \ + lnkctl2_tls == PCI_EXP_LNKCTL2_TLS_8_0GT ? PCIE_SPEED_8_0GT : \ + lnkctl2_tls == PCI_EXP_LNKCTL2_TLS_5_0GT ? PCIE_SPEED_5_0GT : \ + lnkctl2_tls == PCI_EXP_LNKCTL2_TLS_2_5GT ? PCIE_SPEED_2_5GT : \ + PCI_SPEED_UNKNOWN); \ +}) /* PCIe speed to Mb/s reduced by encoding overhead */ #define PCIE_SPEED2MBS_ENC(speed) \