[PATCH v9 10/10] iommu/vt-d: Use old irte in kdump kernel

[Li, Zhen-Hua]

Fix the intr-remapping fault.

[1.594890] dmar: DRHD: handling fault status reg 2
[1.594894] dmar: INTR-REMAP: Request device [[41:00.0] fault index 4d
[1.594894] INTR-REMAP:[fault reason 34] Present field in the IRTE entry
is clear

Use old irte in kdump kernel, do not disable and re-enable interrupt
remapping.

Signed-off-by: Li, Zhen-Hua <zhen-h...@hp.com>
---
 drivers/iommu/intel_irq_remapping.c | 43 +++++++++++++++++++++++++++++++------
 1 file changed, 37 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/intel_irq_remapping.c 
b/drivers/iommu/intel_irq_remapping.c
index 20c060b..4e5a02d 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -199,6 +199,11 @@ static int modify_irte(int irq, struct irte *irte_modified)
 
        set_64bit(&irte->low, irte_modified->low);
        set_64bit(&irte->high, irte_modified->high);
+
+#ifdef CONFIG_CRASH_DUMP
+       if (is_kdump_kernel())
+               __iommu_update_old_irte(iommu, index);
+#endif
        __iommu_flush_cache(iommu, irte, sizeof(*irte));
 
        rc = qi_flush_iec(iommu, index, 0);
@@ -260,6 +265,11 @@ static int clear_entries(struct irq_2_iommu *irq_iommu)
        bitmap_release_region(iommu->ir_table->bitmap, index,
                              irq_iommu->irte_mask);
 
+#ifdef CONFIG_CRASH_DUMP
+       if (is_kdump_kernel())
+               __iommu_update_old_irte(iommu, -1);
+#endif
+
        return qi_flush_iec(iommu, index, irq_iommu->irte_mask);
 }
 
@@ -662,11 +672,20 @@ static int __init intel_enable_irq_remapping(void)
                 */
                dmar_fault(-1, iommu);
 
-               /*
-                * Disable intr remapping and queued invalidation, if already
-                * enabled prior to OS handover.
-                */
-               iommu_disable_irq_remapping(iommu);
+#ifdef CONFIG_CRASH_DUMP
+               if (is_kdump_kernel()) {
+                       /* Do notdisable irq and then re-enable again. */
+               } else {
+#endif
+                       /*
+                        * Disable intr remapping and queued invalidation,
+                        * if already enabled prior to OS handover.
+                        */
+                       iommu_disable_irq_remapping(iommu);
+
+#ifdef CONFIG_CRASH_DUMP
+               }
+#endif
 
                dmar_disable_qi(iommu);
        }
@@ -702,7 +721,19 @@ static int __init intel_enable_irq_remapping(void)
         * Setup Interrupt-remapping for all the DRHD's now.
         */
        for_each_iommu(iommu, drhd) {
-               iommu_set_irq_remapping(iommu, eim);
+#ifdef CONFIG_CRASH_DUMP
+               if (is_kdump_kernel()) {
+                       unsigned long long q;
+
+                       q = dmar_readq(iommu->reg + DMAR_IRTA_REG);
+                       iommu->ir_table->base_old_phys = q & VTD_PAGE_MASK;
+                       iommu->ir_table->base_old_virt = ioremap_cache(
+                               iommu->ir_table->base_old_phys,
+                               INTR_REMAP_TABLE_ENTRIES*sizeof(struct irte));
+                       __iommu_load_old_irte(iommu);
+               } else
+#endif
+                       iommu_set_irq_remapping(iommu, eim);
                setup = 1;
        }
 
-- 
2.0.0-rc0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/