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 DD3182EC090; Tue, 12 May 2026 18:11:49 +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=1778609509; cv=none; b=PvMrrBwl/408w7z/JFxz9bbDjRQIw6sTXDOruWbSiBW4T+oBFCdfuo7EB9UHHijIxxim6OHpY4G1e9TEr1suEojjHzuSQzvZ6bQOSyaRuEqihuRnj0QCa7OQPQgu9gOpeabKJ0i2EZbEMMqj60JXg6yqXSqWiWzSYYRNO7ux2b4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778609509; c=relaxed/simple; bh=xOPMv1t9vdFcK4H53HFM6aI4+1MTapg6y48Vg+PGL1A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mw3cnsIthEF8zRqDWOkINGCrpd2iL0i/kRiU1569QUxgyRMequVN7EGnQnaWmyxlpQ5VsQrFlErym/VCXd5hzwK3oa4+mf5ydXxMRqFRYmtLm5txqcGDbMsMJqrFYpmtF9T/tcdkUiBaCsHF3nUFs49UNlmM4lqjkBqoGogZVf0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=y1gzcBcP; 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="y1gzcBcP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74893C2BCB0; Tue, 12 May 2026 18:11:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778609509; bh=xOPMv1t9vdFcK4H53HFM6aI4+1MTapg6y48Vg+PGL1A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=y1gzcBcPjXbje7HqnXYjnbvgmiPNzgs76l/vnKwBzMVDyLQ9ALATJgFadQ5n9O0D1 M0NukByLnXF1NPisxSKaylGBbOcOtpJq2SKNEIANu67pVJJtfNIqbMrY35igY8MWhE lvvXOpA7eaf8Tq+sdJmxWvtskL/sUkedFK+cCZfc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Lukas Wunner , Shuai Xue , Bjorn Helgaas , Kuppuswamy Sathyanarayanan Subject: [PATCH 7.0 223/307] PCI/AER: Clear only error bits in PCIe Device Status Date: Tue, 12 May 2026 19:40:18 +0200 Message-ID: <20260512173944.825802299@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260512173940.117428952@linuxfoundation.org> References: <20260512173940.117428952@linuxfoundation.org> User-Agent: quilt/0.69 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-Transfer-Encoding: 8bit 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Shuai Xue commit a8aeea1bf3c80cc87983689e0118770e019bd4f3 upstream. Currently, pcie_clear_device_status() clears the entire PCIe Device Status register (PCI_EXP_DEVSTA) by writing back the value read from the register, which affects not only the error status bits but also other writable bits. According to PCIe r7.0, sec 7.5.3.5, this register contains: - RW1C error status bits (CED, NFED, FED, URD at bits 0-3): These are the four error status bits that need to be cleared. - Read-only bits (AUXPD at bit 4, TRPND at bit 5): Writing to these has no effect. - Emergency Power Reduction Detected (bit 6): A RW1C non-error bit introduced in PCIe r5.0 (2019). This is currently the only writable non-error bit in the Device Status register. Unconditionally clearing this bit can interfere with other software components that rely on this power management indication. - Reserved bits (RsvdZ): These bits are required to be written as zero. Writing 1s to them (as the current implementation may do) violates the specification. To prevent unintended side effects, modify pcie_clear_device_status() to only write 1s to the four error status bits (CED, NFED, FED, URD), leaving the Emergency Power Reduction Detected bit and reserved bits unaffected. Fixes: ec752f5d54d7 ("PCI/AER: Clear device status bits during ERR_FATAL and ERR_NONFATAL") Suggested-by: Lukas Wunner Signed-off-by: Shuai Xue Signed-off-by: Bjorn Helgaas Reviewed-by: Kuppuswamy Sathyanarayanan Reviewed-by: Lukas Wunner Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260211124624.49656-1-xueshuai@linux.alibaba.com Signed-off-by: Greg Kroah-Hartman --- drivers/pci/pci.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2241,10 +2241,9 @@ EXPORT_SYMBOL_GPL(pci_set_pcie_reset_sta #ifdef CONFIG_PCIEAER void pcie_clear_device_status(struct pci_dev *dev) { - u16 sta; - - pcie_capability_read_word(dev, PCI_EXP_DEVSTA, &sta); - pcie_capability_write_word(dev, PCI_EXP_DEVSTA, sta); + pcie_capability_write_word(dev, PCI_EXP_DEVSTA, + PCI_EXP_DEVSTA_CED | PCI_EXP_DEVSTA_NFED | + PCI_EXP_DEVSTA_FED | PCI_EXP_DEVSTA_URD); } #endif