[PATCH] x86_64: Fix CONFIG_IOMMU_DEBUG

If CONFIG_IOMMU_DEBUG is set force_iommu defaults to 1. In the case
where no HW IOMMU is present in the machine and we end up using nommu,
leaving force_iommu set to 1 causes dma_alloc_coherent to do the wrong
thing. Therefore, if we end up using nommu, make sure force_iommu is
0.

Signed-off-by: Muli Ben-Yehuda <[e-mail]>
Signed-off-by: Andi Kleen <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

arch/x86_64/kernel/pci-nommu.c

···
 {
 	if (dma_ops)
 		return;
+
+	force_iommu = 0; /* no HW IOMMU */
 	dma_ops = &nommu_dma_ops;
 }