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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 C32F9C2D0DB for ; Tue, 28 Jan 2020 14:09:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 98A2B22522 for ; Tue, 28 Jan 2020 14:09:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580220553; bh=wdwwvVSenVt6N8xdd9g8pLjeeMvBztVrT/ceq7bgBaM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Q378gIdH9AzZRmRlxAwjSqdhak9puUTPtb+G3QfUtLbtMx/BzC3h3DouGR7LWvLLt p5eSmAE1CXENHTrf90CQAuspHRYnaMOvKJ+MMceKBhLAad+xES9yOcxnuGNmuwAaB7 DKuYlk4pFc+YB3leIvuoDHFx96s8LSNeOTVwhH3g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727823AbgA1OJM (ORCPT ); Tue, 28 Jan 2020 09:09:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:57252 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728607AbgA1OI7 (ORCPT ); Tue, 28 Jan 2020 09:08:59 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D195922522; Tue, 28 Jan 2020 14:08:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580220539; bh=wdwwvVSenVt6N8xdd9g8pLjeeMvBztVrT/ceq7bgBaM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UfwPWkqSQUZoNUq7pB8rbUO1tZ0t8RUjhJCUl6obQJg/ZyjANagdLHNM0aUA8gViI na1TIqtt0OMfqKCrmzNTt7mDelWQcf6CWpvf2tI3MsqQzhgu02lWaNWNafppYDr8ZJ 7eDhYD9GhT4Q9/zTzh7bdNPZ7nkQ+ixQfIgN/0zo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Auger , Alex Williamson , Sasha Levin Subject: [PATCH 4.4 048/183] vfio_pci: Enable memory accesses before calling pci_map_rom Date: Tue, 28 Jan 2020 15:04:27 +0100 Message-Id: <20200128135834.766684922@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200128135829.486060649@linuxfoundation.org> References: <20200128135829.486060649@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 4b62eb3b59233..7a82735d53087 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