[PATCH] AMD IOMMU: initialize IOMMU when GART is detected

[PATCH] AMD IOMMU: initialize IOMMU when GART is detected

[Joerg Roedel]

One of the last IOMMU updates covered a bug in the AMD IOMMU code. The early
detection code does not succeed if the GART is already detected. This patch
fixes this by removing the check for iommu_detected in the early detect code.
On AMD systems only the GART code sets this variable to one beside the AMD
IOMMU driver.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
---
 arch/x86/kernel/amd_iommu_init.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
index 2a13e43..71e13af 100644
--- a/arch/x86/kernel/amd_iommu_init.c
+++ b/arch/x86/kernel/amd_iommu_init.c
@@ -828,7 +828,7 @@ static int __init early_amd_iommu_detect(struct acpi_table_header *table)
 
 void __init amd_iommu_detect(void)
 {
-	if (swiotlb || no_iommu || iommu_detected)
+	if (swiotlb || no_iommu)
 		return;
 
 	if (acpi_table_parse("IVRS", early_amd_iommu_detect) == 0) {
-- 
1.5.3.7

Re: [PATCH] AMD IOMMU: initialize IOMMU when GART is detected

[Joerg Roedel]

On Mon, Jul 07, 2008 at 04:42:50PM +0200, Joerg Roedel wrote:
> One of the last IOMMU updates covered a bug in the AMD IOMMU code. The early
> detection code does not succeed if the GART is already detected. This patch
> fixes this by removing the check for iommu_detected in the early detect code.
> On AMD systems only the GART code sets this variable to one beside the AMD
> IOMMU driver.
> 
> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
> ---
>  arch/x86/kernel/amd_iommu_init.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
> index 2a13e43..71e13af 100644
> --- a/arch/x86/kernel/amd_iommu_init.c
> +++ b/arch/x86/kernel/amd_iommu_init.c
> @@ -828,7 +828,7 @@ static int __init early_amd_iommu_detect(struct acpi_table_header *table)
>  
>  void __init amd_iommu_detect(void)
>  {
> -	if (swiotlb || no_iommu || iommu_detected)
> +	if (swiotlb || no_iommu)
>  		return;
>  
>  	if (acpi_table_parse("IVRS", early_amd_iommu_detect) == 0) {

Argh. I posted the wrong version of the patch. Please ignore this one. I
will send an updated one.

Joerg

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