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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 2BCE2C33CAF for ; Thu, 16 Jan 2020 17:56:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0881D2073A for ; Thu, 16 Jan 2020 17:56:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579197400; bh=rO9MRv8YhSyyoMyG5psAWUEUdC5BhENMela2iZyySFM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=MJtucXoYmeGILXQKNB5MmrxOhjWDSGtDVo3K2IaGC5sjSqy5dGkYIe5rP+25rwKIj qUbueZlC6H9EaShuntSSlOHQi23flkW5J/hvK+pvPCcNlLRBq3YkD1meMCYNk0hfRk t4LwbnjQuhEdei/CnAY70RF/Z4p1Ue8ytlrihPto= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406223AbgAPR4c (ORCPT ); Thu, 16 Jan 2020 12:56:32 -0500 Received: from mail.kernel.org ([198.145.29.99]:34420 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2394018AbgAPRnx (ORCPT ); Thu, 16 Jan 2020 12:43:53 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8B0F62469C; Thu, 16 Jan 2020 17:43:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579196633; bh=rO9MRv8YhSyyoMyG5psAWUEUdC5BhENMela2iZyySFM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OdW3audGyD4SAepaIpUtVm8seXjSXCMX7pRabt5ri8HWERWHErCHAYXtt43f1+UHK BaZHmN7K0D0rYkA3bt4AuvSX3eaklx2h3JNJwi1K6tCZWTMJIa3nK5qfwntQZ2OnH+ Ab2wu9dWGZmFdheMM7Fqf8TwtnJZgQ2sfJ/1fs7c= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Auger , Alex Williamson , Sasha Levin , kvm@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 046/174] vfio_pci: Enable memory accesses before calling pci_map_rom Date: Thu, 16 Jan 2020 12:40:43 -0500 Message-Id: <20200116174251.24326-46-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116174251.24326-1-sashal@kernel.org> References: <20200116174251.24326-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Eric Auger [ Upstream commit 0cfd027be1d6def4a462cdc180c055143af24069 ] pci_map_rom/pci_get_rom_size() performs memory access in the ROM. In case the Memory Space accesses were disabled, readw() is likely to trigger a synchronous external abort on some platforms. In case memory accesses were disabled, re-enable them before the call and disable them back again just after. Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver") Signed-off-by: Eric Auger Suggested-by: Alex Williamson Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin --- drivers/vfio/pci/vfio_pci.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 4b62eb3b5923..7a82735d5308 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -496,6 +496,7 @@ static long vfio_pci_ioctl(void *device_data, { void __iomem *io; size_t size; + u16 orig_cmd; info.offset = VFIO_PCI_INDEX_TO_OFFSET(info.index); info.flags = 0; @@ -505,15 +506,23 @@ static long vfio_pci_ioctl(void *device_data, if (!info.size) break; - /* Is it really there? */ + /* + * Is it really there? Enable memory decode for + * implicit access in pci_map_rom(). + */ + pci_read_config_word(pdev, PCI_COMMAND, &orig_cmd); + pci_write_config_word(pdev, PCI_COMMAND, + orig_cmd | PCI_COMMAND_MEMORY); + io = pci_map_rom(pdev, &size); - if (!io || !size) { + if (io) { + info.flags = VFIO_REGION_INFO_FLAG_READ; + pci_unmap_rom(pdev, io); + } else { info.size = 0; - break; } - pci_unmap_rom(pdev, io); - info.flags = VFIO_REGION_INFO_FLAG_READ; + pci_write_config_word(pdev, PCI_COMMAND, orig_cmd); break; } case VFIO_PCI_VGA_REGION_INDEX: -- 2.20.1