[Xen-devel] [PATCH 1/2] AMD IOMMU: also spot missing IO-APIC entries in IVRS table

["Jan Beulich" <JBeulich@xxxxxxxx>]

Apart from dealing duplicate conflicting entries, we also have to
handle firmware omitting IO-APIC entries in IVRS altogether. Not doing
so has resulted in c/s 26517:601139e2b0db to crash such systems during
boot (whereas with the change here the IOMMU gets disabled just as is
being done in the other cases, i.e. unless global tables are being
used).

Debugging this issue has also pointed out that the debug log output is
pretty ugly to look at - consolidate the output, and add one extra
item for the IVHD special entries, so that future issues are easier
to analyze.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Tested-by: Sander Eikelenboom <linux@xxxxxxxxxxxxxx>

--- a/xen/drivers/passthrough/amd/iommu_acpi.c
+++ b/xen/drivers/passthrough/amd/iommu_acpi.c
@@ -354,9 +354,8 @@ static int __init parse_ivmd_block(const
     base = start_addr & PAGE_MASK;
     limit = (start_addr + mem_length - 1) & PAGE_MASK;
 
-    AMD_IOMMU_DEBUG("IVMD Block: Type %#x\n",ivmd_block->header.type);
-    AMD_IOMMU_DEBUG(" Start_Addr_Phys %#lx\n", start_addr);
-    AMD_IOMMU_DEBUG(" Mem_Length %#lx\n", mem_length);
+    AMD_IOMMU_DEBUG("IVMD Block: type %#x phys %#lx len %#lx\n",
+                    ivmd_block->header.type, start_addr, mem_length);
 
     if ( ivmd_block->header.flags & ACPI_IVMD_EXCLUSION_RANGE )
         iw = ir = IOMMU_CONTROL_ENABLED;
@@ -551,8 +550,8 @@ static u16 __init parse_ivhd_device_alia
         return 0;
     }
 
-    AMD_IOMMU_DEBUG(" Dev_Id Range: %#x -> %#x\n", first_bdf, last_bdf);
-    AMD_IOMMU_DEBUG(" Dev_Id Alias: %#x\n", alias_id);
+    AMD_IOMMU_DEBUG(" Dev_Id Range: %#x -> %#x alias %#x\n",
+                    first_bdf, last_bdf, alias_id);
 
     for ( bdf = first_bdf; bdf <= last_bdf; bdf++ )
         add_ivrs_mapping_entry(bdf, alias_id, range->alias.header.data_setting,
@@ -654,6 +653,9 @@ static u16 __init parse_ivhd_device_spec
         return 0;
     }
 
+    AMD_IOMMU_DEBUG("IVHD Special: %04x:%02x:%02x.%u variety %#x handle %#x\n",
+                    seg, PCI_BUS(bdf), PCI_SLOT(bdf), PCI_FUNC(bdf),
+                    special->variety, special->handle);
     add_ivrs_mapping_entry(bdf, bdf, special->header.data_setting, iommu);
 
     switch ( special->variety )
@@ -758,10 +760,9 @@ static int __init parse_ivhd_block(const
     {
         ivhd_device = (const void *)((const u8 *)ivhd_block + block_length);
 
-        AMD_IOMMU_DEBUG( "IVHD Device Entry:\n");
-        AMD_IOMMU_DEBUG( " Type %#x\n", ivhd_device->header.type);
-        AMD_IOMMU_DEBUG( " Dev_Id %#x\n", ivhd_device->header.id);
-        AMD_IOMMU_DEBUG( " Flags %#x\n", ivhd_device->header.data_setting);
+        AMD_IOMMU_DEBUG("IVHD Device Entry: type %#x id %#x flags %#x\n",
+                        ivhd_device->header.type, ivhd_device->header.id,
+                        ivhd_device->header.data_setting);
 
         switch ( ivhd_device->header.type )
         {
@@ -890,6 +891,7 @@ static int __init parse_ivrs_table(struc
 {
     const struct acpi_ivrs_header *ivrs_block;
     unsigned long length;
+    unsigned int apic;
     int error = 0;
 
     BUG_ON(!table);
@@ -903,11 +905,9 @@ static int __init parse_ivrs_table(struc
     {
         ivrs_block = (struct acpi_ivrs_header *)((u8 *)table + length);
 
-        AMD_IOMMU_DEBUG("IVRS Block:\n");
-        AMD_IOMMU_DEBUG(" Type %#x\n", ivrs_block->type);
-        AMD_IOMMU_DEBUG(" Flags %#x\n", ivrs_block->flags);
-        AMD_IOMMU_DEBUG(" Length %#x\n", ivrs_block->length);
-        AMD_IOMMU_DEBUG(" Dev_Id %#x\n", ivrs_block->device_id);
+        AMD_IOMMU_DEBUG("IVRS Block: type %#x flags %#x len %#x id %#x\n",
+                        ivrs_block->type, ivrs_block->flags,
+                        ivrs_block->length, ivrs_block->device_id);
 
         if ( table->length < (length + ivrs_block->length) )
         {
@@ -922,6 +922,29 @@ static int __init parse_ivrs_table(struc
         length += ivrs_block->length;
     }
 
+    /* Each IO-APIC must have been mentioned in the table. */
+    for ( apic = 0; !error && apic < nr_ioapics; ++apic )
+    {
+        if ( !nr_ioapic_entries[apic] ||
+             ioapic_sbdf[IO_APIC_ID(apic)].pin_setup )
+            continue;
+
+        printk(XENLOG_ERR "IVHD Error: no information for IO-APIC %#x\n",
+               IO_APIC_ID(apic));
+        if ( amd_iommu_perdev_intremap )
+            error = -ENXIO;
+        else
+        {
+            ioapic_sbdf[IO_APIC_ID(apic)].pin_setup = xzalloc_array(
+                unsigned long, BITS_TO_LONGS(nr_ioapic_entries[apic]));
+            if ( !ioapic_sbdf[IO_APIC_ID(apic)].pin_setup )
+            {
+                printk(XENLOG_ERR "IVHD Error: Out of memory\n");
+                error = -ENOMEM;
+            }
+        }
+    }
+
     return error;
 }

Attachment: AMD-IOMMU-IVHD-special-missing.patch
Description: Text document

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