src/patches/suse-2.6.27.25/patches.arch/x2APIC_PATCH_04_f12c73e7fa7ebf9ad6defee2c4fb2664e743e970

   1 From: Yinghai Lu <yhlu.kernel@gmail.com>
   2 Subject: dmar: fix using early fixmap mapping for DMAR table parsing
   3 References: fate #303948 and fate #303984
   4 Patch-Mainline: queued for .28
   5 Commit-ID: f12c73e7fa7ebf9ad6defee2c4fb2664e743e970
   6
   7 Signed-off-by: Thomas Renninger <trenn@suse.de>
   8
   9 Very early detection of the DMAR tables will setup fixmap mapping. For
  10 parsing these tables later (while enabling dma and/or interrupt remapping),
  11 early fixmap mapping shouldn't be used. Fix it by calling table detection
  12 routines again, which will call generic apci_get_table() for setting up
  13 the correct mapping.
  14
  15 Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
  16 Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
  17 Signed-off-by: Ingo Molnar <mingo@elte.hu>
  18
  19 ---
  20  drivers/pci/dmar.c   |   49 ++++++++++++++++++++++++++++---------------------
  21  include/linux/dmar.h |    1 -
  22  2 files changed, 28 insertions(+), 22 deletions(-)
  23
  24 Index: linux-2.6.26/drivers/pci/dmar.c
  25 ===================================================================
  26 --- linux-2.6.26.orig/drivers/pci/dmar.c
  27 +++ linux-2.6.26/drivers/pci/dmar.c
  28 @@ -289,6 +289,24 @@ dmar_table_print_dmar_entry(struct acpi_
  29         }
  30  }
  31
  32 +/**
  33 + * dmar_table_detect - checks to see if the platform supports DMAR devices
  34 + */
  35 +static int __init dmar_table_detect(void)
  36 +{
  37 +       acpi_status status = AE_OK;
  38 +
  39 +       /* if we could find DMAR table, then there are DMAR devices */
  40 +       status = acpi_get_table(ACPI_SIG_DMAR, 0,
  41 +                               (struct acpi_table_header **)&dmar_tbl);
  42 +
  43 +       if (ACPI_SUCCESS(status) && !dmar_tbl) {
  44 +               printk (KERN_WARNING PREFIX "Unable to map DMAR\n");
  45 +               status = AE_NOT_FOUND;
  46 +       }
  47 +
  48 +       return (ACPI_SUCCESS(status) ? 1 : 0);
  49 +}
  50
  51  /**
  52   * parse_dmar_table - parses the DMA reporting table
  53 @@ -300,6 +318,12 @@ parse_dmar_table(void)
  54         struct acpi_dmar_header *entry_header;
  55         int ret = 0;
  56
  57 +       /*
  58 +        * Do it again, earlier dmar_tbl mapping could be mapped with
  59 +        * fixed map.
  60 +        */
  61 +       dmar_table_detect();
  62 +
  63         dmar = (struct acpi_table_dmar *)dmar_tbl;
  64         if (!dmar)
  65                 return -ENODEV;
  66 @@ -432,30 +456,11 @@ int __init dmar_table_init(void)
  67         return 0;
  68  }
  69
  70 -/**
  71 - * early_dmar_detect - checks to see if the platform supports DMAR devices
  72 - */
  73 -int __init early_dmar_detect(void)
  74 -{
  75 -       acpi_status status = AE_OK;
  76 -
  77 -       /* if we could find DMAR table, then there are DMAR devices */
  78 -       status = acpi_get_table(ACPI_SIG_DMAR, 0,
  79 -                               (struct acpi_table_header **)&dmar_tbl);
  80 -
  81 -       if (ACPI_SUCCESS(status) && !dmar_tbl) {
  82 -               printk (KERN_WARNING PREFIX "Unable to map DMAR\n");
  83 -               status = AE_NOT_FOUND;
  84 -       }
  85 -
  86 -       return (ACPI_SUCCESS(status) ? 1 : 0);
  87 -}
  88 -
  89  void __init detect_intel_iommu(void)
  90  {
  91         int ret;
  92
  93 -       ret = early_dmar_detect();
  94 +       ret = dmar_table_detect();
  95
  96  #ifdef CONFIG_DMAR
  97         {
  98 @@ -481,14 +486,16 @@ void __init detect_intel_iommu(void)
  99                                " x2apic support\n");
 100
 101                         dmar_disabled = 1;
 102 -                       return;
 103 +                       goto end;
 104                 }
 105
 106                 if (ret && !no_iommu && !iommu_detected && !swiotlb &&
 107                     !dmar_disabled)
 108                         iommu_detected = 1;
 109         }
 110 +end:
 111  #endif
 112 +       dmar_tbl = NULL;
 113  }
 114
 115
 116 Index: linux-2.6.26/include/linux/dmar.h
 117 ===================================================================
 118 --- linux-2.6.26.orig/include/linux/dmar.h
 119 +++ linux-2.6.26/include/linux/dmar.h
 120 @@ -45,7 +45,6 @@ extern struct list_head dmar_drhd_units;
 121         list_for_each_entry(drhd, &dmar_drhd_units, list)
 122
 123  extern int dmar_table_init(void);
 124 -extern int early_dmar_detect(void);
 125  extern int dmar_dev_scope_init(void);
 126
 127  /* Intel IOMMU detection */