x86, io_apic: Introduce x86_io_apic_ops.print_entries for debugging

This call-back is used to dump IO-APIC entries for debugging
purposes into the kernel log. VT-d needs a special routine
for this and will overwrite the default.

Signed-off-by: Joerg Roedel <joro@8bytes.org>
Acked-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index af8904de1d44..cb9a72d4cc09 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -617,6 +617,14 @@ static int __init intel_enable_irq_remapping(void)
                 goto error;
 
         irq_remapping_enabled = 1;
+
+        /*
+         * VT-d has a different layout for IO-APIC entries when
+         * interrupt remapping is enabled. So it needs a special routine
+         * to print IO-APIC entries for debugging purposes too.
+         */
+        x86_io_apic_ops.print_entries = intel_ir_io_apic_print_entries;
+
         pr_info("Enabled IRQ remapping in %s mode\n", eim ? "x2apic" : "xapic");
 
         return eim ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;