From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:50034 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754473AbdKMNAm (ORCPT ); Mon, 13 Nov 2017 08:00:42 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nate Watterson , Will Deacon , Sasha Levin Subject: [PATCH 4.9 13/87] iommu/arm-smmu-v3: Clear prior settings when updating STEs Date: Mon, 13 Nov 2017 13:55:30 +0100 Message-Id: <20171113125616.452473993@linuxfoundation.org> In-Reply-To: <20171113125615.304035578@linuxfoundation.org> References: <20171113125615.304035578@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nate Watterson [ Upstream commit 810871c57011eb3e89e6768932757f169d666cd2 ] To prevent corruption of the stage-1 context pointer field when updating STEs, rebuild the entire containing dword instead of clearing individual fields. Signed-off-by: Nate Watterson Signed-off-by: Will Deacon Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/iommu/arm-smmu-v3.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1040,13 +1040,8 @@ static void arm_smmu_write_strtab_ent(st } } - /* Nuke the existing Config, as we're going to rewrite it */ - val &= ~(STRTAB_STE_0_CFG_MASK << STRTAB_STE_0_CFG_SHIFT); - - if (ste->valid) - val |= STRTAB_STE_0_V; - else - val &= ~STRTAB_STE_0_V; + /* Nuke the existing STE_0 value, as we're going to rewrite it */ + val = ste->valid ? STRTAB_STE_0_V : 0; if (ste->bypass) { val |= disable_bypass ? STRTAB_STE_0_CFG_ABORT @@ -1081,7 +1076,6 @@ static void arm_smmu_write_strtab_ent(st val |= (ste->s1_cfg->cdptr_dma & STRTAB_STE_0_S1CTXPTR_MASK << STRTAB_STE_0_S1CTXPTR_SHIFT) | STRTAB_STE_0_CFG_S1_TRANS; - } if (ste->s2_cfg) {