From patchwork Tue Apr 2 01:33:07 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Vasut X-Patchwork-Id: 10880895 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E1BA51800 for ; Tue, 2 Apr 2019 01:33:43 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D55AC287FA for ; Tue, 2 Apr 2019 01:33:43 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C9C0C28837; Tue, 2 Apr 2019 01:33:43 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 69EC5287FB for ; Tue, 2 Apr 2019 01:33:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728743AbfDBBdm (ORCPT ); Mon, 1 Apr 2019 21:33:42 -0400 Received: from mail-pl1-f194.google.com ([209.85.214.194]:36633 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726163AbfDBBdm (ORCPT ); Mon, 1 Apr 2019 21:33:42 -0400 Received: by mail-pl1-f194.google.com with SMTP id ck15so4182048plb.3; Mon, 01 Apr 2019 18:33:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=JY5xYvCLwwUJvsda8ccnmMiMiuKZ9i5E/Z+FL52T01g=; b=m3GSkY0d973a0yQqcjly2/+V1nBDvENMqqsV83T8La7gAdrMSjvIgStoZJsx7obkkR 9uz6Z2UMZ3fFtCtVlL/xZ05+YzPFMm+CQhvkvkvgkAzTYoCVj05K+LKCUJSvPVojFDKQ 8A7LIYbaDeE9b6UQTJJ9KOZbitJV4lKOaIUagGjS1RGL5clmxFk87JmXnVM7Yh+G/pKq GT9D5T1OP5WZIqw+G+n6XMhWoROAsWfJ0e9VE+85ODg+XRUDkyXbeS3C9+rQYdIEtf/2 eqkkRP0Wzg1qYUhIbZmdZg1XHobe721lsFkx3W66+Idc1ypcZGec+5o/oXyv/elu3rwZ DC4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=JY5xYvCLwwUJvsda8ccnmMiMiuKZ9i5E/Z+FL52T01g=; b=JLfR/896f2Dp0cNJy0NAs5oEWQxBxhIOm/q5oiyK6XTM1qZKMKZ8WqYy2OGC0e1zVB P0CdrN5DKcNJcd5QDlUEgPXr3ubOMx/6QxlhRMEMmaqI4rnN/Q6hiiao01kentktZGUY 71ts65DdbD8g/A3hCCsq8cobSiI2mL98xZzbUzkIHqlBLpu10D0JAZvuMtLGwrC5ASQz xXAm5nTwwSHZwXChlIIjGbTZruLYTtpejCXwZZF+mZcSBoWMux09OwNL/KkXH1svOeMn 9KABqttRfOv8fGXoJuULLezrX+7mZch0CDPuoyRm1kfBQwG5sQ+CvR5Ef7V2q7zliBlv 5TeQ== X-Gm-Message-State: APjAAAVXl0Xpoz4WrKmqXl5EAmH6HmlFOLlwKlIXMssEXl8bbORdbfV0 Ny1z3LdChzJfZme8/lkea8zIIrEt X-Google-Smtp-Source: APXvYqx01p8g/bATZsjXE77HrNQKOlVkb4aXFdJM5jTjGEEy5ZNP6Kw3+EKdaheo3QfvFkoLmKnDDg== X-Received: by 2002:a17:902:e091:: with SMTP id cb17mr43867136plb.222.1554168821697; Mon, 01 Apr 2019 18:33:41 -0700 (PDT) Received: from localhost.localdomain ([1.1.125.76]) by smtp.gmail.com with ESMTPSA id q86sm27912247pfi.171.2019.04.01.18.33.38 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 01 Apr 2019 18:33:40 -0700 (PDT) From: marek.vasut@gmail.com To: linux-pci@vger.kernel.org Cc: Marek Vasut , Geert Uytterhoeven , Phil Edworthy , Simon Horman , Wolfram Sang , linux-renesas-soc@vger.kernel.org Subject: [PATCH V5 6/6] PCI: rcar: Fix 64bit MSI message address handling Date: Tue, 2 Apr 2019 03:33:07 +0200 Message-Id: <20190402013307.20912-6-marek.vasut@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190402013307.20912-1-marek.vasut@gmail.com> References: <20190402013307.20912-1-marek.vasut@gmail.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Marek Vasut The MSI message address in the RC address space can be 64 bit. The R-Car PCIe RC supports such a 64bit MSI message address as well. The code currently uses virt_to_phys(__get_free_pages()) to obtain a reserved page for the MSI message address, and the return value of which can be a 64 bit physical address on 64 bit system. However, the driver only programs PCIEMSIALR register with the bottom 32 bits of the virt_to_phys(__get_free_pages()) return value and does not program the top 32 bits into PCIEMSIAUR, but rather programs the PCIEMSIAUR register with 0x0. This worked fine on older 32 bit R-Car SoCs, however may fail on new 64 bit R-Car SoCs. Since from a PCIe controller perspective, an inbound MSI is a memory write to a special address (in case of this controller, defined by the value in PCIEMSIAUR:PCIEMSIALR), which triggers an interrupt, but never hits the DRAM _and_ because allocation of an MSI by a PCIe card driver obtains the MSI message address by reading PCIEMSIAUR:PCIEMSIALR in rcar_msi_setup_irqs(), incorrectly programmed PCIEMSIAUR cannot cause memory corruption or other issues. There is however the possibility that if virt_to_phys(__get_free_pages()) returned address above the 32bit boundary _and_ PCIEMSIAUR was programmed to 0x0 _and_ if the system had physical RAM at the address matching the value of PCIEMSIALR, a PCIe card driver could allocate a buffer with a physical address matching the value of PCIEMSIALR and a remote write to such a buffer by a PCIe card would trigger a spurious MSI. Signed-off-by: Marek Vasut Cc: Geert Uytterhoeven Cc: Phil Edworthy Cc: Simon Horman Cc: Wolfram Sang Cc: linux-renesas-soc@vger.kernel.org To: linux-pci@vger.kernel.org Reviewed-by: Geert Uytterhoeven Reviewed-by: Wolfram Sang Reviewed-by: Simon Horman --- V2: - s/it's/its/ in commit message - Add R-B from Geert V3: - Reworded commit message and thus dropped Geerts R-B V4: - Add Geert's R-B again V5: - Rebase on next/master 20190401 - Use {lower,upper}_32_bits() instead of >> 32 --- drivers/pci/controller/pcie-rcar.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c index 168bc6b9bb93..5e0102796345 100644 --- a/drivers/pci/controller/pcie-rcar.c +++ b/drivers/pci/controller/pcie-rcar.c @@ -892,7 +892,7 @@ static int rcar_pcie_enable_msi(struct rcar_pcie *pcie) { struct device *dev = pcie->dev; struct rcar_msi *msi = &pcie->msi; - unsigned long base; + phys_addr_t base; int err, i; mutex_init(&msi->lock); @@ -933,8 +933,8 @@ static int rcar_pcie_enable_msi(struct rcar_pcie *pcie) msi->pages = __get_free_pages(GFP_KERNEL, 0); base = virt_to_phys((void *)msi->pages); - rcar_pci_write_reg(pcie, base | MSIFE, PCIEMSIALR); - rcar_pci_write_reg(pcie, 0, PCIEMSIAUR); + rcar_pci_write_reg(pcie, lower_32_bits(base) | MSIFE, PCIEMSIALR); + rcar_pci_write_reg(pcie, upper_32_bits(base), PCIEMSIAUR); /* enable all MSI interrupts */ rcar_pci_write_reg(pcie, 0xffffffff, PCIEMSIIER);