From: Muli Ben-Yehuda <muli@il.ibm.com>
Date: Wed, 2 Aug 2006 20:37:31 +0000 (+0200)
Subject: [PATCH] x86_64: Fix CONFIG_IOMMU_DEBUG
X-Git-Tag: v2.6.18-rc4~68
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a166222cde740b34d97fe49dca70348197f4534e;p=linux-2.6

[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 <muli@il.ibm.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/arch/x86_64/kernel/pci-nommu.c b/arch/x86_64/kernel/pci-nommu.c
index c4c3cc36ac..aad7609d8e 100644
--- a/arch/x86_64/kernel/pci-nommu.c
+++ b/arch/x86_64/kernel/pci-nommu.c
@@ -92,5 +92,7 @@ void __init no_iommu_init(void)
 {
 	if (dma_ops)
 		return;
+
+	force_iommu = 0; /* no HW IOMMU */
 	dma_ops = &nommu_dma_ops;
 }