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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 972FEC32751 for ; Sat, 10 Aug 2019 20:53:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7461F2086A for ; Sat, 10 Aug 2019 20:53:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727457AbfHJUxO (ORCPT ); Sat, 10 Aug 2019 16:53:14 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:53910 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726515AbfHJUnt (ORCPT ); Sat, 10 Aug 2019 16:43:49 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hwYDK-00053u-9q; Sat, 10 Aug 2019 21:43:46 +0100 Received: from ben by deadeye with local (Exim 4.92) (envelope-from ) id 1hwYDJ-0003aU-ID; Sat, 10 Aug 2019 21:43:45 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Ashok Raj" , "Joerg Roedel" , "mark gross" , "Lu Baolu" , "Jacob Pan" Date: Sat, 10 Aug 2019 21:40:07 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 038/157] iommu/vt-d: Check capability before disabling protected memory In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.72-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Lu Baolu commit 5bb71fc790a88d063507dc5d445ab8b14e845591 upstream. The spec states in 10.4.16 that the Protected Memory Enable Register should be treated as read-only for implementations not supporting protected memory regions (PLMR and PHMR fields reported as Clear in the Capability register). Cc: Jacob Pan Cc: mark gross Suggested-by: Ashok Raj Fixes: f8bab73515ca5 ("intel-iommu: PMEN support") Signed-off-by: Lu Baolu Signed-off-by: Joerg Roedel Signed-off-by: Ben Hutchings --- drivers/iommu/intel-iommu.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -1394,6 +1394,9 @@ static void iommu_disable_protect_mem_re u32 pmen; unsigned long flags; + if (!cap_plmr(iommu->cap) && !cap_phmr(iommu->cap)) + return; + raw_spin_lock_irqsave(&iommu->register_lock, flags); pmen = readl(iommu->reg + DMAR_PMEN_REG); pmen &= ~DMA_PMEN_EPM;