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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6BA12C43334 for ; Wed, 13 Jul 2022 20:51:52 +0000 (UTC) Received: from localhost ([::1]:42930 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oBjKp-0004i9-DD for qemu-devel@archiver.kernel.org; Wed, 13 Jul 2022 16:51:51 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:53058) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oBfwT-0006dl-6R; Wed, 13 Jul 2022 13:14:29 -0400 Received: from imap4.hz.codethink.co.uk ([188.40.203.114]:38714) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oBfwR-0003CY-Lk; Wed, 13 Jul 2022 13:14:28 -0400 Received: from cpc152649-stkp13-2-0-cust121.10-2.cable.virginm.net ([86.15.83.122] helo=rainbowdash) by imap4.hz.codethink.co.uk with esmtpsa (Exim 4.94.2 #2 (Debian)) id 1oBfdU-003M8o-18; Wed, 13 Jul 2022 17:54:51 +0100 Received: from ben by rainbowdash with local (Exim 4.96) (envelope-from ) id 1oBfdS-0009kn-1k; Wed, 13 Jul 2022 17:54:50 +0100 From: Ben Dooks To: qemu-devel@nongnu.org Cc: qemu-arm@nongnu.org, Jude Onyenegecha , Sudip Mukherjee , William Salmon , Adnan Chowdhury , Ben Dooks Subject: [PATCH 3/7] pci: designware: clamp viewport index Date: Wed, 13 Jul 2022 17:54:45 +0100 Message-Id: <20220713165449.37433-4-ben.dooks@sifive.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220713165449.37433-1-ben.dooks@sifive.com> References: <20220713165449.37433-1-ben.dooks@sifive.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=188.40.203.114; envelope-from=ben@codethink.co.uk; helo=imap4.hz.codethink.co.uk X-Spam_score_int: -16 X-Spam_score: -1.7 X-Spam_bar: - X-Spam_report: (-1.7 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-Mailman-Approved-At: Wed, 13 Jul 2022 16:45:29 -0400 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The current Linux driver for this assumes it can write the 255 into this register and then read back the value to work out how many viewports are supported. Clamp the value so that the probe works and does not cause memory corruption as the value is not well clamped elsewhere in the driver. Signed-off-by: Ben Dooks --- hw/pci-host/designware.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/hw/pci-host/designware.c b/hw/pci-host/designware.c index d213d7324c..6403416634 100644 --- a/hw/pci-host/designware.c +++ b/hw/pci-host/designware.c @@ -345,6 +345,10 @@ static void designware_pcie_root_config_write(PCIDevice *d, uint32_t address, break; case DESIGNWARE_PCIE_ATU_VIEWPORT: + /* clamp this value, linux uses it to calculate the + * available number of viewports */ + if (val >= DESIGNWARE_PCIE_NUM_VIEWPORTS) + val = DESIGNWARE_PCIE_NUM_VIEWPORTS-1; root->atu_viewport = val; break; -- 2.35.1