From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D3D28C4338F for ; Mon, 16 Aug 2021 08:16:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B12F061B04 for ; Mon, 16 Aug 2021 08:16:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234552AbhHPIRN (ORCPT ); Mon, 16 Aug 2021 04:17:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:43618 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234386AbhHPIRN (ORCPT ); Mon, 16 Aug 2021 04:17:13 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D7F7261AFD; Mon, 16 Aug 2021 08:16:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1629101802; bh=LV6d+Q2+R8BoCReXw22uBvg4HRr1sCVX532m6/LEpbk=; h=Subject:To:Cc:From:Date:From; b=n77AxPdfjRKBTUrOOM1NDjLX3wpJkx9gixxLqogG/dWtX5iFL6dyGMqs19hXx1Dbg ld9WZQJeYFG2TzvJvNtiU/OJuQCit2aNx/0u0yS5GAOo7sO2Gtl0kNpwLStQtq5rBc GXgJGdV+bJAajg7MNOD0Wv3xzfua9vTd5dK7LDlQ= Subject: FAILED: patch "[PATCH] PCI/MSI: Enforce that MSI-X table entry is masked for update" failed to apply to 4.14-stable tree To: tglx@linutronix.de, bhelgaas@google.com, kevin.tian@intel.com, maz@kernel.org Cc: From: Date: Mon, 16 Aug 2021 10:16:30 +0200 Message-ID: <16291017902272@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.14-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 . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From da181dc974ad667579baece33c2c8d2d1e4558d5 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 29 Jul 2021 23:51:42 +0200 Subject: [PATCH] PCI/MSI: Enforce that MSI-X table entry is masked for update The specification (PCIe r5.0, sec 6.1.4.5) states: For MSI-X, a function is permitted to cache Address and Data values from unmasked MSI-X Table entries. However, anytime software unmasks a currently masked MSI-X Table entry either by clearing its Mask bit or by clearing the Function Mask bit, the function must update any Address or Data values that it cached from that entry. If software changes the Address or Data value of an entry while the entry is unmasked, the result is undefined. The Linux kernel's MSI-X support never enforced that the entry is masked before the entry is modified hence the Fixes tag refers to a commit in: git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Enforce the entry to be masked across the update. There is no point in enforcing this to be handled at all possible call sites as this is just pointless code duplication and the common update function is the obvious place to enforce this. Fixes: f036d4ea5fa7 ("[PATCH] ia32 Message Signalled Interrupt support") Reported-by: Kevin Tian Signed-off-by: Thomas Gleixner Tested-by: Marc Zyngier Reviewed-by: Marc Zyngier Acked-by: Bjorn Helgaas Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210729222542.462096385@linutronix.de diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 57c9ec9b976b..7ee1ac47caa7 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -289,13 +289,28 @@ void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg) /* Don't touch the hardware now */ } else if (entry->msi_attrib.is_msix) { void __iomem *base = pci_msix_desc_addr(entry); + bool unmasked = !(entry->masked & PCI_MSIX_ENTRY_CTRL_MASKBIT); if (!base) goto skip; + /* + * The specification mandates that the entry is masked + * when the message is modified: + * + * "If software changes the Address or Data value of an + * entry while the entry is unmasked, the result is + * undefined." + */ + if (unmasked) + __pci_msix_desc_mask_irq(entry, PCI_MSIX_ENTRY_CTRL_MASKBIT); + writel(msg->address_lo, base + PCI_MSIX_ENTRY_LOWER_ADDR); writel(msg->address_hi, base + PCI_MSIX_ENTRY_UPPER_ADDR); writel(msg->data, base + PCI_MSIX_ENTRY_DATA); + + if (unmasked) + __pci_msix_desc_mask_irq(entry, 0); } else { int pos = dev->msi_cap; u16 msgctl;