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 F3F062472B4; Tue, 29 Apr 2025 17:26:00 +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=1745947561; cv=none; b=dQMVWBvWjHbyBRaU3wfi9yTy5O46zEZWJGrDTZxte4/dPYCayC4w2oJ0hWIcLoVyTQ/HZpdg0cztG7rS5Sa8GWdFF5917lXn6chKDepQKe51haldVAn8CmMzaCfw/1EmEh+5FgQdwlauG4JBIgzfz8bfTS97rOt+wKpxwwAqDs8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745947561; c=relaxed/simple; bh=oOxa3RHSm1m6XBLnziJuO+wqvVOdO9EqlhUNHpdUSko=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mVtp8ZJKDBGBslng1sPvxKKJ9WRzHTxKC5/Bq/DXiBrY12eejsza+qgzipZMOy+7IVdtBPkyLZ0EJMZrR5M06tJ15mijAP3RdJpRVONFYmRrfhWcY9DQLIZ8ZZb4oGPBgfGnAHrt+XF33lN6DpPR/nTHCowhmIt7esq2A8qChp8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Cgz0gkFq; 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="Cgz0gkFq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6ADEDC4CEE3; Tue, 29 Apr 2025 17:26:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745947560; bh=oOxa3RHSm1m6XBLnziJuO+wqvVOdO9EqlhUNHpdUSko=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Cgz0gkFqLK27ImJq3aoG8hnKu7OMQguO4Ihscr8tpnske0iny4esmWwcL8CyI28iJ ivvvJ9tAuS4iMaoyztdJOJff6CTldvWIag4CfbupRBc02ftpuhp7q9Fal5yEmDXxPE /A+puF6xlk56R4XL4DXqR3EIq6YJCfPRonHDu7PY= 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 6.12 033/280] PCI/MSI: Add an option to write MSIX ENTRY_DATA before any reads Date: Tue, 29 Apr 2025 18:39:34 +0200 Message-ID: <20250429161116.476657228@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250429161115.008747050@linuxfoundation.org> References: <20250429161115.008747050@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-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 74114acbb07fb..ade889ded4e1e 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