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 988AD263C9B for ; Mon, 21 Apr 2025 11:26:35 +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=1745234795; cv=none; b=qyCzZIwxp9xEq86nOHd0PpOLKxMOQMxp+TIfOMmtWlCnMnp78cgHXykVpGUmzvUI8wtdkxXTHgeyD5uFZhL9JTKz+rxSG8gDpeqLkS3RuhwEZZ9Ypcm46gJyPs5Rz5pN1t7KCS8MBbCxYm29aB+mN70GnE0Bee7Ww06GcRgKb1c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745234795; c=relaxed/simple; bh=idpiqp/n3j48NWmhnRxyE+IHTZ5ruS2SRckUVXYdw6k=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=j9M/9xozY/SgFMHGiZ2ilRnN1yjQAgNUFj7uBozmBVmE6EcLeYK/i8TuPyr1E7mz19MVSIYLnFIc6oVcTsXen/9K//mFQ2bCzTj7D5ExZE/JgjMnu2Y5kAExtuvqIMw4DwepCMEDaqEVR3Y6fo/Bi+7g7DXzHjRpNYBoyCgOhoc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=iYBEhhc6; 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="iYBEhhc6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1EA3CC4CEE4; Mon, 21 Apr 2025 11:26:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745234795; bh=idpiqp/n3j48NWmhnRxyE+IHTZ5ruS2SRckUVXYdw6k=; h=Subject:To:Cc:From:Date:From; b=iYBEhhc6oBJDcXuuDfx0Xz1Nk1ATmCvAfRYXKmmEzfUSotHKqSt8VQ69I2Uiro2tY hocLH+gjJ3VjuiILC2dzChAUY/viVTJWeXPeU6yAzyLAlISUM/MNX0BKSSXk6TYBdq Qa2PEwk5/18OXZAEqMGieyWaSHY1InDSMbpOzSew= Subject: FAILED: patch "[PATCH] PCI/MSI: Add an option to write MSIX ENTRY_DATA before any" failed to apply to 5.4-stable tree To: dullfire@yahoo.com,tglx@linutronix.de Cc: From: Date: Mon, 21 Apr 2025 13:26:21 +0200 Message-ID: <2025042121-bullfrog-dean-00a2@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.4-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 . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x cf761e3dacc6ad5f65a4886d00da1f9681e6805a # git commit -s git send-email --to '' --in-reply-to '2025042121-bullfrog-dean-00a2@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From cf761e3dacc6ad5f65a4886d00da1f9681e6805a Mon Sep 17 00:00:00 2001 From: Jonathan Currier Date: Sun, 17 Nov 2024 17:48:42 -0600 Subject: [PATCH] PCI/MSI: Add an option to write MSIX ENTRY_DATA before any reads 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 diff --git a/drivers/pci/msi/msi.c b/drivers/pci/msi/msi.c index 6569ba3577fe..8b8848788618 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 0e8e3fd77e96..51e2bd6405cd 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 {