From mboxrd@z Thu Jan 1 00:00:00 1970 From: Baoquan He Subject: Re: [PATCH v5 5/8] iommu/amd: copy old trans table from old kernel Date: Wed, 28 Sep 2016 09:37:02 +0800 Message-ID: <20160928013702.GH14155@x1.redhat.com> References: <1473951806-25511-1-git-send-email-bhe@redhat.com> <1473951806-25511-6-git-send-email-bhe@redhat.com> <20160920124031.GD3541@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20160920124031.GD3541-zLv9SwRftAIdnm+yROfE0A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Joerg Roedel Cc: kexec-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Vincent.Wan-5C7GfCeVMHo@public.gmane.org, iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, dyoung-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org List-Id: iommu@lists.linux-foundation.org Hi Joerg, On 09/20/16 at 02:40pm, Joerg Roedel wrote: > > + 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...)? Did you mean wraping iommu_feature_disable(iommu, CONTROL_CMDBUF_EN) into a helper function like iommu_disable_command_buffer(), and wraping iommu_feature_disable(iommu, CONTROL_EVT_LOG_EN) into iommu_disable_event_buffer()? I retest with not disabling command buffer and event log here, it works on amd iommu v1 and v2 systems. So if I understand your comment correctly, there's no need to add "iommu_feature_disable(iommu, CONTROL_CMDBUF_EN)" and "iommu_feature_disable(iommu, CONTROL_EVT_LOG_EN)" here. I remember I added them here because more IO_PAGE_FAULT messages are printed without them. But now it seems not to related to them. So I will remove above two lines of code. > > > + 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 > >