Messages in this thread Patch in this message | | | From | Greg Kroah-Hartman <> | Subject | [PATCH 4.14 187/343] iommu/vt-d: Make kernel parameter igfx_off work with vIOMMU | Date | Fri, 24 Jan 2020 10:30:05 +0100 |
| |
From: Lu Baolu <baolu.lu@linux.intel.com>
[ Upstream commit 5daab58043ee2bca861068e2595564828f3bc663 ]
The kernel parameter igfx_off is used by users to disable DMA remapping for the Intel integrated graphic device. It was designed for bare metal cases where a dedicated IOMMU is used for graphic. This doesn't apply to virtual IOMMU case where an include-all IOMMU is used. This makes the kernel parameter work with virtual IOMMU as well.
Cc: Ashok Raj <ashok.raj@intel.com> Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> Suggested-by: Kevin Tian <kevin.tian@intel.com> Fixes: c0771df8d5297 ("intel-iommu: Export a flag indicating that the IOMMU is used for iGFX.") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Tested-by: Zhenyu Wang <zhenyuw@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/iommu/intel-iommu.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 523d0889c2a4e..4fbd183d973ab 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -3361,9 +3361,12 @@ static int __init init_dmars(void) iommu_identity_mapping |= IDENTMAP_ALL; #ifdef CONFIG_INTEL_IOMMU_BROKEN_GFX_WA - iommu_identity_mapping |= IDENTMAP_GFX; + dmar_map_gfx = 0; #endif + if (!dmar_map_gfx) + iommu_identity_mapping |= IDENTMAP_GFX; + check_tylersburg_isoch(); if (iommu_identity_mapping) { -- 2.20.1
| |