From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753843AbcITMkk (ORCPT ); Tue, 20 Sep 2016 08:40:40 -0400 Received: from 8bytes.org ([81.169.241.247]:34402 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752028AbcITMki (ORCPT ); Tue, 20 Sep 2016 08:40:38 -0400 Date: Tue, 20 Sep 2016 14:40:31 +0200 From: Joerg Roedel To: Baoquan He Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org, dyoung@redhat.com, xlpang@redhat.com, Vincent.Wan@amd.com Subject: Re: [PATCH v5 5/8] iommu/amd: copy old trans table from old kernel Message-ID: <20160920124031.GD3541@8bytes.org> References: <1473951806-25511-1-git-send-email-bhe@redhat.com> <1473951806-25511-6-git-send-email-bhe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1473951806-25511-6-git-send-email-bhe@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Sep 15, 2016 at 11:03:23PM +0800, Baoquan He wrote: > Here several things need be done: > 1) If iommu is pre-enabled in a normal kernel, just disable it and print > warning. > 2) If failed to copy dev table of old kernel, continue to proceed as > it does in normal kernel. > 3) Re-enable event/cmd buffer and install the new DTE table to reg. > 4) Flush all caches > > Signed-off-by: Baoquan He > --- > drivers/iommu/amd_iommu_init.c | 44 +++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 41 insertions(+), 3 deletions(-) > > diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c > index ce49641..47a8fc9 100644 > --- a/drivers/iommu/amd_iommu_init.c > +++ b/drivers/iommu/amd_iommu_init.c > @@ -34,7 +34,7 @@ > #include > #include > #include > - > +#include Please keep that empty line, it is there for readability. > #include "amd_iommu_proto.h" > #include "amd_iommu_types.h" > #include "irq_remapping.h" > @@ -1344,6 +1344,12 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h) > iommu->int_enabled = false; > > init_translation_status(iommu); > + if (translation_pre_enabled(iommu) && !is_kdump_kernel()) { > + iommu_disable(iommu); > + clear_translation_pre_enabled(iommu); > + pr_warn("Translation was enabled for IOMMU:%d but we are not in kdump mode\n", > + iommu->index); > + } > > if (translation_pre_enabled(iommu)) > pr_warn("Translation is already enabled - trying to copy translation structures\n"); > @@ -1946,9 +1952,41 @@ static void early_enable_iommu(struct amd_iommu *iommu) > static void early_enable_iommus(void) > { > struct amd_iommu *iommu; > + bool is_pre_enabled=false; > > - for_each_iommu(iommu) > - early_enable_iommu(iommu); > + for_each_iommu(iommu) { > + if ( translation_pre_enabled(iommu) ) { Coding style, too many spaces. There is more of that below. > + is_pre_enabled = true; > + break; > + } > + } > + > + if ( !is_pre_enabled) { > + for_each_iommu(iommu) > + early_enable_iommu(iommu); > + } else { > + if (copy_dev_tables()) { > + pr_err("Failed to copy DEV table from previous kernel.\n"); > + /* > + * If failed to copy dev tables from old kernel, continue to proceed > + * as it does in normal kernel. > + */ > + for_each_iommu(iommu) { > + clear_translation_pre_enabled(iommu); > + early_enable_iommu(iommu); > + } > + } else { > + pr_info("Copied DEV table from previous kernel.\n"); > + for_each_iommu(iommu) { > + iommu_feature_disable(iommu, CONTROL_CMDBUF_EN); > + iommu_feature_disable(iommu, CONTROL_EVT_LOG_EN); Could you move that into new helpers (iommu_disable_command_buffer...)? > + iommu_enable_command_buffer(iommu); > + iommu_enable_event_buffer(iommu); > + iommu_set_device_table(iommu); > + iommu_flush_all_caches(iommu); > + } > + } > + } > } > > static void enable_iommus_v2(void) > -- > 2.5.5 >