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

Li, Zhen-Hua
2015-03-19T05:38:07Z

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-hual@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