From 3ce1f93c6d53c3f91c3846cf66b018276c8ac2e7 Mon Sep 17 00:00:00 2001 From: Joerg Roedel <joerg.roedel@amd.com> Date: Mon, 17 Nov 2008 15:09:20 +0100 Subject: [PATCH] AMD IOMMU: enable device isolation per default 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 <joerg.roedel@amd.com> --- Documentation/kernel-parameters.txt | 2 +- arch/x86/kernel/amd_iommu_init.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index b56ee02d25148..f2e1e7fc0ffd9 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -294,7 +294,7 @@ and is between 256 and 4096 characters. It is defined in the file Possible values are: isolate - enable device isolation (each device, as far as possible, will get its own protection - domain) + domain) [default] share - put every device behind one IOMMU into the same protection domain fullflush - enable flushing of IO/TLB entries when diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c index 838a2e1d5bb29..595edd2befc66 100644 --- a/arch/x86/kernel/amd_iommu_init.c +++ b/arch/x86/kernel/amd_iommu_init.c @@ -121,7 +121,7 @@ u16 amd_iommu_last_bdf; /* largest PCI device id we have 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 */ bool amd_iommu_unmap_flush; /* if true, flush on every unmap */ LIST_HEAD(amd_iommu_list); /* list of all AMD IOMMUs in the -- GitLab