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=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 BE4C1C32771 for ; Fri, 24 Jan 2020 11:25:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 926832077C for ; Fri, 24 Jan 2020 11:25:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579865118; bh=Vv9erbEQQGavVsx826/tDXV2+GO6A1Maocox5xDS/ic=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=nsOYltZ8cXSYoGnwc6dKpEbYWYMwuBN0eOUovtd4Y4/gYc25Hyvl5udZ5wY/rO9sz XssQOeEkvFgJZWaWAICRivQOBLXCJ+3bVtqBnuogNGeXIKA4p6OyrGAm7m7ojdzfOl fDlqAxLmBYosoialWIhorvRcL7oIAARHZ1WNup7I= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391472AbgAXLZR (ORCPT ); Fri, 24 Jan 2020 06:25:17 -0500 Received: from mail.kernel.org ([198.145.29.99]:39196 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391458AbgAXLZN (ORCPT ); Fri, 24 Jan 2020 06:25:13 -0500 Received: from localhost (ip-213-127-102-57.ip.prioritytelecom.net [213.127.102.57]) (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 4BE3F206D4; Fri, 24 Jan 2020 11:25:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579865113; bh=Vv9erbEQQGavVsx826/tDXV2+GO6A1Maocox5xDS/ic=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=itw01S6HSMqG/N++8h5WJTdre59pf7Ga26PwAi+lMxCvDQ6hNN/SMRL1sbPh0oZxk vqxnTRFCXmHvP7m5412S3yTdaW/un/jv63skLxjsmFB1B8znmEXokHmu9j4zZ8kXmk A9L7imw3nhsF/bXaG5Bn1PSuV3s/u4J8k4fkDmvs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kevin Mitchell , Joerg Roedel , Sasha Levin Subject: [PATCH 4.19 457/639] iommu/amd: Make iommu_disable safer Date: Fri, 24 Jan 2020 10:30:27 +0100 Message-Id: <20200124093144.438370856@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124093047.008739095@linuxfoundation.org> References: <20200124093047.008739095@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: Kevin Mitchell [ Upstream commit 3ddbe913e55516d3e2165d43d4d5570761769878 ] Make it safe to call iommu_disable during early init error conditions before mmio_base is set, but after the struct amd_iommu has been added to the amd_iommu_list. For example, this happens if firmware fails to fill in mmio_phys in the ACPI table leading to a NULL pointer dereference in iommu_feature_disable. Fixes: 2c0ae1720c09c ('iommu/amd: Convert iommu initialization to state machine') Signed-off-by: Kevin Mitchell Signed-off-by: Joerg Roedel Signed-off-by: Sasha Levin --- drivers/iommu/amd_iommu_init.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c index 1e9a5da562f0d..465f28a7844c2 100644 --- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -422,6 +422,9 @@ static void iommu_enable(struct amd_iommu *iommu) static void iommu_disable(struct amd_iommu *iommu) { + if (!iommu->mmio_base) + return; + /* Disable command buffer */ iommu_feature_disable(iommu, CONTROL_CMDBUF_EN); -- 2.20.1