diff options
| author | Kyle McMartin <kyle@redhat.com> | 2009-02-04 14:29:19 -0800 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-02-05 16:48:38 +0100 |
| commit | 0cd5c3c80a0ebd68c08312fa7d8c13149cc61c4c (patch) | |
| tree | 4dc6093ee08e668a182b38bd13cd85436555c4b6 | |
| parent | b534816b552d35bbd3c60702139ed5c7da2f55c2 (diff) | |
x86: disable intel_iommu support by default
Due to recurring issues with DMAR support on certain platforms.
There's a number of filesystem corruption incidents reported:
https://bugzilla.redhat.com/show_bug.cgi?id=479996
http://bugzilla.kernel.org/show_bug.cgi?id=12578
Provide a Kconfig option to change whether it is enabled by
default.
If disabled, it can still be reenabled by passing intel_iommu=on to the
kernel. Keep the .config option off by default.
Signed-off-by: Kyle McMartin <kyle@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-By: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | Documentation/kernel-parameters.txt | 2 | ||||
| -rw-r--r-- | arch/x86/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/pci/intel-iommu.c | 14 |
3 files changed, 24 insertions, 3 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index d8362cf9909..b182626739e 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -937,6 +937,8 @@ and is between 256 and 4096 characters. It is defined in the file intel_iommu= [DMAR] Intel IOMMU driver (DMAR) option + on + Enable intel iommu driver. off Disable intel iommu driver. igfx_off [Default Off] diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 73f7fe8fd4d..9c39095b33f 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1802,6 +1802,17 @@ config DMAR and include PCI device scope covered by these DMA remapping devices. +config DMAR_DEFAULT_ON + def_bool n + prompt "Enable DMA Remapping Devices by default" + depends on DMAR + help + Selecting this option will enable a DMAR device at boot time if + one is found. If this option is not selected, DMAR support can + be enabled by passing intel_iommu=on to the kernel. It is + recommended you say N here while the DMAR code remains + experimental. + config DMAR_GFX_WA def_bool y prompt "Support for Graphics workaround" diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index 3dfecb20d5e..f4b7c79023f 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -268,7 +268,12 @@ static long list_size; static void domain_remove_dev_info(struct dmar_domain *domain); -int dmar_disabled; +#ifdef CONFIG_DMAR_DEFAULT_ON +int dmar_disabled = 0; +#else +int dmar_disabled = 1; +#endif /*CONFIG_DMAR_DEFAULT_ON*/ + static int __initdata dmar_map_gfx = 1; static int dmar_forcedac; static int intel_iommu_strict; @@ -284,9 +289,12 @@ static int __init intel_iommu_setup(char *str) if (!str) return -EINVAL; while (*str) { - if (!strncmp(str, "off", 3)) { + if (!strncmp(str, "on", 2)) { + dmar_disabled = 0; + printk(KERN_INFO "Intel-IOMMU: enabled\n"); + } else if (!strncmp(str, "off", 3)) { dmar_disabled = 1; - printk(KERN_INFO"Intel-IOMMU: disabled\n"); + printk(KERN_INFO "Intel-IOMMU: disabled\n"); } else if (!strncmp(str, "igfx_off", 8)) { dmar_map_gfx = 0; printk(KERN_INFO |