2.6.27-stable review patch. If anyone has any objections, please let us know. ------------------ From: Joerg Roedel commit 3ce1f93c6d53c3f91c3846cf66b018276c8ac2e7 upstream. Impact: makes device isolation the default for AMD IOMMU Some device drivers showed double-free bugs of DMA memory while testing them with AMD IOMMU. If all devices share the same protection domain this can lead to data corruption and data loss. Prevent this by putting each device into its own protection domain per default. Signed-off-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman --- Documentation/kernel-parameters.txt | 2 +- arch/x86/kernel/amd_iommu_init.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -120,7 +120,7 @@ u16 amd_iommu_last_bdf; /* largest PCI LIST_HEAD(amd_iommu_unity_map); /* a list of required unity mappings we find in ACPI */ unsigned amd_iommu_aperture_order = 26; /* size of aperture in power of 2 */ -int amd_iommu_isolate; /* if 1, device isolation is enabled */ +int amd_iommu_isolate = 1; /* if 1, device isolation is enabled */ LIST_HEAD(amd_iommu_list); /* list of all AMD IOMMUs in the system */ --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -283,7 +283,7 @@ and is between 256 and 4096 characters. Possible values are: isolate - enable device isolation (each device, as far as possible, will get its own protection - domain) + domain) [default] amd_iommu_size= [HW,X86-64] Define the size of the aperture for the AMD IOMMU driver. Possible values are: