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 0D92321772B; Tue, 29 Apr 2025 16:56:33 +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=1745945794; cv=none; b=LAEu05n+MIe6xDkAnSAu8yJB1oHusiUhL/8T9LJ3+T3rdH5Hc7PPtemxp6QbYHm589BulFaQEGqh94IHJJwdSuOSiwCPovIm6NuH4PXcjLnHzDhWPivcyDyv/D2jZWfpwxNAVYScN6b2I0MZHQucLcVnTAGEW6ho9fgH5x8UHsI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745945794; c=relaxed/simple; bh=WvZqEz/kxPQAKPJV/KuvQ+boxgFPTz3/1j1hDCNQu5o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mu9xHVQtT13+or36YMSwAjbwvakeaoD05xUAqv7/O3zYZtZhGNiMcpPRPlRBXQl3hSYg+7eqg4a8Xn7BgRCbpsl9Q9HEB71zXMeuk2bEz47GzxmVmI+REG6rLFJyDMV+z/IMtCERC37ntwgUx2pQlUQbNEuaFi7hkkJhURY21aM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=WyrFyVAK; 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="WyrFyVAK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 77648C4CEE3; Tue, 29 Apr 2025 16:56:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745945793; bh=WvZqEz/kxPQAKPJV/KuvQ+boxgFPTz3/1j1hDCNQu5o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WyrFyVAKtn2OH5bTD7UvrFnC7qaT/Qd8XtPmZvgzZhSC8NGjWgiY0Cagpxz+LLOAx d57o0v/aK6Y9T8BtVoJnZE5Z3XbB/djQ/p9aXuBXhsamstXeQ8a4G1pfekkQ9EFx7C RE2MhakEsGHMFI6dVtNtUvUpnUGc3Rs1knETeegE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jonathan Currier , Thomas Gleixner , Sasha Levin Subject: [PATCH 6.14 022/311] PCI/MSI: Add an option to write MSIX ENTRY_DATA before any reads Date: Tue, 29 Apr 2025 18:37:39 +0200 Message-ID: <20250429161121.939605191@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250429161121.011111832@linuxfoundation.org> References: <20250429161121.011111832@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-Transfer-Encoding: 8bit 6.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jonathan Currier [ Upstream commit cf761e3dacc6ad5f65a4886d00da1f9681e6805a ] Commit 7d5ec3d36123 ("PCI/MSI: Mask all unused MSI-X entries") introduced a readl() from ENTRY_VECTOR_CTRL before the writel() to ENTRY_DATA. This is correct, however some hardware, like the Sun Neptune chips, the NIU module, will cause an error and/or fatal trap if any MSIX table entry is read before the corresponding ENTRY_DATA field is written to. Add an optional early writel() in msix_prepare_msi_desc(). Fixes: 7d5ec3d36123 ("PCI/MSI: Mask all unused MSI-X entries") Signed-off-by: Jonathan Currier Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20241117234843.19236-2-dullfire@yahoo.com Signed-off-by: Sasha Levin --- drivers/pci/msi/msi.c | 3 +++ include/linux/pci.h | 2 ++ 2 files changed, 5 insertions(+) diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c index 6569ba3577fe6..8b88487886184 100644 --- a/drivers/pci/msi/msi.c +++ b/drivers/pci/msi/msi.c @@ -615,6 +615,9 @@ void msix_prepare_msi_desc(struct pci_dev *dev, struct msi_desc *desc) void __iomem *addr = pci_msix_desc_addr(desc); desc->pci.msi_attrib.can_mask = 1; + /* Workaround for SUN NIU insanity, which requires write before read */ + if (dev->dev_flags & PCI_DEV_FLAGS_MSIX_TOUCH_ENTRY_DATA_FIRST) + writel(0, addr + PCI_MSIX_ENTRY_DATA); desc->pci.msix_ctrl = readl(addr + PCI_MSIX_ENTRY_VECTOR_CTRL); } } diff --git a/include/linux/pci.h b/include/linux/pci.h index 47b31ad724fa5..8e028620642f3 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -245,6 +245,8 @@ enum pci_dev_flags { PCI_DEV_FLAGS_NO_RELAXED_ORDERING = (__force pci_dev_flags_t) (1 << 11), /* Device does honor MSI masking despite saying otherwise */ PCI_DEV_FLAGS_HAS_MSI_MASKING = (__force pci_dev_flags_t) (1 << 12), + /* Device requires write to PCI_MSIX_ENTRY_DATA before any MSIX reads */ + PCI_DEV_FLAGS_MSIX_TOUCH_ENTRY_DATA_FIRST = (__force pci_dev_flags_t) (1 << 13), }; enum pci_irq_reroute_variant { -- 2.39.5