[PATCH v10 10/10] iommu/vt-d: Use old irte in kdump kernel

From: Li, Zhen-Hua
Date: Fri Apr 10 2015 - 04:44:32 EST


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 second kernel, do not disable and re-enable interrupt
remapping.

Signed-off-by: Li, Zhen-Hua <zhen-hual@xxxxxx>
---
drivers/iommu/intel_irq_remapping.c | 28 ++++++++++++++++++++++++----
1 file changed, 24 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index e6426a0..02615a6 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -197,6 +197,10 @@ static int modify_irte(int irq, struct irte *irte_modified)

set_64bit(&irte->low, irte_modified->low);
set_64bit(&irte->high, irte_modified->high);
+
+ if (iommu->pre_enabled_ir)
+ __iommu_update_old_irte(iommu, index);
+
__iommu_flush_cache(iommu, irte, sizeof(*irte));

rc = qi_flush_iec(iommu, index, 0);
@@ -258,6 +262,9 @@ static int clear_entries(struct irq_2_iommu *irq_iommu)
bitmap_release_region(iommu->ir_table->bitmap, index,
irq_iommu->irte_mask);

+ if (iommu->pre_enabled_ir)
+ __iommu_update_old_irte(iommu, -1);
+
return qi_flush_iec(iommu, index, irq_iommu->irte_mask);
}

@@ -660,11 +667,13 @@ static int __init intel_enable_irq_remapping(void)
*/
dmar_fault(-1, iommu);

+ iommu_check_pre_ir_status(iommu);
+
/*
- * Disable intr remapping and queued invalidation, if already
- * enabled prior to OS handover.
+ * Here we do not disable intr remapping,
+ * if already enabled prior to OS handover.
*/
- iommu_disable_irq_remapping(iommu);
+ /* iommu_disable_irq_remapping(iommu); */

dmar_disable_qi(iommu);
}
@@ -700,7 +709,18 @@ 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);
+ if (iommu->pre_enabled_ir) {
+ 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
+ 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 majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/