From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933544AbZIDJpY (ORCPT ); Fri, 4 Sep 2009 05:45:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S933476AbZIDJpU (ORCPT ); Fri, 4 Sep 2009 05:45:20 -0400 Received: from va3ehsobe003.messaging.microsoft.com ([216.32.180.13]:21490 "EHLO VA3EHSOBE003.bigfish.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S933340AbZIDJpQ (ORCPT ); Fri, 4 Sep 2009 05:45:16 -0400 X-SpamScore: 3 X-BigFish: VPS3(zzzz1202hzzz32i203h43j62h) X-Spam-TCS-SCL: 1:0 X-FB-SS: 5, X-WSS-ID: 0KPFXRA-04-HZQ-01 From: Joerg Roedel To: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org CC: Joerg Roedel Subject: [PATCH 7/8] x86/amd-iommu: Panic if IOMMU command buffer reset fails Date: Fri, 4 Sep 2009 11:44:41 +0200 Message-ID: <1252057482-32207-8-git-send-email-joerg.roedel@amd.com> X-Mailer: git-send-email 1.6.3.3 In-Reply-To: <1252057482-32207-1-git-send-email-joerg.roedel@amd.com> References: <1252057482-32207-1-git-send-email-joerg.roedel@amd.com> X-OriginalArrivalTime: 04 Sep 2009 09:44:45.0429 (UTC) FILETIME=[55D15A50:01CA2D44] MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org To prevent the driver from doing recursive command buffer resets, just panic when that recursion happens. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/amd_iommu_types.h | 3 +++ arch/x86/kernel/amd_iommu.c | 7 +++++++ 2 files changed, 10 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h index c54bc97..e676746 100644 --- a/arch/x86/include/asm/amd_iommu_types.h +++ b/arch/x86/include/asm/amd_iommu_types.h @@ -337,6 +337,9 @@ struct amd_iommu { /* if one, we need to send a completion wait command */ bool need_sync; + /* becomes true if a command buffer reset is running */ + bool reset_in_progress; + /* default dma_ops domain for that IOMMU */ struct dma_ops_domain *default_dom; }; diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c index 2333d61..b62a2f6 100644 --- a/arch/x86/kernel/amd_iommu.c +++ b/arch/x86/kernel/amd_iommu.c @@ -553,9 +553,16 @@ static void reset_iommu_command_buffer(struct amd_iommu *iommu) { pr_err("AMD-Vi: Resetting IOMMU command buffer\n"); + if (iommu->reset_in_progress) + panic("AMD-Vi: ILLEGAL_COMMAND_ERROR while resetting command buffer\n"); + + iommu->reset_in_progress = true; + amd_iommu_reset_cmd_buffer(iommu); flush_all_devices_for_iommu(iommu); flush_all_domains_on_iommu(iommu); + + iommu->reset_in_progress = false; } /**************************************************************************** -- 1.6.3.3