>From 7d60445b9ba0c447a3f027470bed7a7c680f73c9 Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Thu, 7 Mar 2019 13:14:43 +0800 Subject: [PATCH 08/12] iommu/vt-d: Enable DMA remapping after rmrr mapped The rmrr devices require identity map of the rmrr regions before enabling DMA remapping. Otherwise, there will be a window during which DMA from/to the rmrr regions will be blocked. In order to alleviate this, we move enabling DMA remapping after all rmrr regions get mapped. Signed-off-by: Lu Baolu --- drivers/iommu/intel-iommu.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index eb8aca8d1dc9..9641d75cbfa3 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -3385,11 +3385,6 @@ static int __init init_dmars(void) ret = dmar_set_interrupt(iommu); if (ret) goto free_iommu; - - if (!translation_pre_enabled(iommu)) - iommu_enable_translation(iommu); - - iommu_disable_protect_mem_regions(iommu); } return 0; @@ -4733,7 +4728,6 @@ int __init intel_iommu_init(void) goto out_free_reserved_range; } up_write(&dmar_global_lock); - pr_info("Intel(R) Virtualization Technology for Directed I/O\n"); #if defined(CONFIG_X86) && defined(CONFIG_SWIOTLB) swiotlb = 0; @@ -4756,6 +4750,16 @@ int __init intel_iommu_init(void) register_memory_notifier(&intel_iommu_memory_nb); cpuhp_setup_state(CPUHP_IOMMU_INTEL_DEAD, "iommu/intel:dead", NULL, intel_iommu_cpu_dead); + + /* Finally, we enable the DMA remapping hardware. */ + for_each_iommu(iommu, drhd) { + if (!translation_pre_enabled(iommu)) + iommu_enable_translation(iommu); + + iommu_disable_protect_mem_regions(iommu); + } + pr_info("Intel(R) Virtualization Technology for Directed I/O\n"); + intel_iommu_enabled = 1; intel_iommu_debugfs_init(); -- 2.17.1