Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1408469

Re: [Patch v4 7/9] iommu/amd: copy old trans table from old kernel

From Wan Zongshun <vw@iommu.org>
Newsgroups linux.kernel
Subject Re: [Patch v4 7/9] iommu/amd: copy old trans table from old kernel
Date 2016-05-28 15:30 +0200
Message-ID <rDMts-ZI-21@gated-at.bofh.it> (permalink)
References <rCAul-619-1@gated-at.bofh.it> <rCAE2-646-17@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw



-------- Original Message --------
> From: Baoquan HE <bhe@dhcp-129-10.nay.redhat.com>
>
> Here several things need be done:
> 1) Initialize amd_iommu_dev_table because it was set several times
>    since kdump kernel reboot. We don't need the set because we will
>    copy the content from old kernel.
> 2) Re-enable event/cmd buffer
> 3) Install the DTE table to reg
> 4) Flush all caches
>
> Signed-off-by: Baoquan He <bhe@redhat.com>
> ---
>  drivers/iommu/amd_iommu_init.c | 47 +++++++++++++++++++++++++++++++++++++-----
>  1 file changed, 42 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
> index 71c7ac9..66a1fa5 100644
> --- a/drivers/iommu/amd_iommu_init.c
> +++ b/drivers/iommu/amd_iommu_init.c
> @@ -35,7 +35,7 @@
>  #include <asm/iommu_table.h>
>  #include <asm/io_apic.h>
>  #include <asm/irq_remapping.h>
> -
> +#include <linux/crash_dump.h>
>  #include "amd_iommu_proto.h"
>  #include "amd_iommu_types.h"
>  #include "irq_remapping.h"
> @@ -675,7 +675,7 @@ static int copy_dev_tables(void)
>  	static int copied;
>
>          for_each_iommu(iommu) {
> -		if (!translation_pre_enabled()) {
> +		if (!translation_pre_enabled(iommu)) {
>  			pr_err("IOMMU:%d is not pre-enabled!/n", iommu->index);
>  			return -1;
>  		}
> @@ -1160,8 +1160,13 @@ 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()) {
> +                        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())
> +	if (translation_pre_enabled(iommu))
>  		pr_warn("Translation is already enabled - trying to copy translation structures\n");
>
>  	ret = init_iommu_from_acpi(iommu, h);
> @@ -1730,9 +1735,41 @@ 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) ) {
> +			is_pre_enabled = true;
> +			break;
> +		}
> +	}

I wonder if you consider multi-iommus condition for your those series 
patches?

> +
> +	if ( !is_pre_enabled) {

Why not use translation_pre_enabled(iommu) to judge pre-enable directly?

> +		for_each_iommu(iommu)
> +			early_enable_iommu(iommu);
> +	} else {
> +		if (copy_dev_tables()) {
> +			pr_err("Failed to copy translation tables 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 translation tables from previous kernel.\n");
> +			for_each_iommu(iommu) {
> +				iommu_feature_disable(iommu, CONTROL_CMDBUF_EN);
> +		                iommu_feature_disable(iommu, CONTROL_EVT_LOG_EN);
> +		                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)
>

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[Patch v4 0/9] *** Fix kdump failure in system with amd iommu*** Baoquan He <bhe@redhat.com> - 2016-05-25 08:30 +0200
  [Patch v4 8/9] iommu/amd: Do not initialize dev tables again in kdump Baoquan He <bhe@redhat.com> - 2016-05-25 08:30 +0200
  [Patch v4 9/9] iommu/amd: Check the validation of irq table and domain id Baoquan He <bhe@redhat.com> - 2016-05-25 08:30 +0200
    Re: [Patch v4 9/9] iommu/amd: Check the validation of irq table and  domain id Wan Zongshun <vw@iommu.org> - 2016-05-28 15:40 +0200
      Re: [Patch v4 9/9] iommu/amd: Check the validation of irq table and  domain id Baoquan He <bhe@redhat.com> - 2016-05-30 07:20 +0200
  [Patch v4 6/9] iommu/amd: Add function copy_dev_tables Baoquan He <bhe@redhat.com> - 2016-05-25 08:30 +0200
    Re: [Patch v4 6/9] iommu/amd: Add function copy_dev_tables Wan Zongshun <vw@iommu.org> - 2016-05-28 15:10 +0200
      Re: [Patch v4 6/9] iommu/amd: Add function copy_dev_tables Baoquan He <bhe@redhat.com> - 2016-05-30 05:40 +0200
  [Patch v4 1/9] iommu/amd: clean up the cmpxchg64 invocation Baoquan He <bhe@redhat.com> - 2016-05-25 08:40 +0200
  [Patch v4 5/9] iommu/amd: Define bit fields for DTE particularly Baoquan He <bhe@redhat.com> - 2016-05-25 08:40 +0200
  [Patch v4 2/9] iommu/amd: Use standard bitmap operation to set bitmap Baoquan He <bhe@redhat.com> - 2016-05-25 08:40 +0200
  [Patch v4 7/9] iommu/amd: copy old trans table from old kernel Baoquan He <bhe@redhat.com> - 2016-05-25 08:40 +0200
    Re: [Patch v4 7/9] iommu/amd: copy old trans table from old kernel Wan Zongshun <vw@iommu.org> - 2016-05-28 15:30 +0200
  Re: [Patch v4 0/9] *** Fix kdump failure in system with amd iommu*** Baoquan He <bhe@redhat.com> - 2016-05-25 09:20 +0200

csiph-web