From: Zhenzhong Duan zhenzhong.duan@gmail.com
[ Upstream commit 4d213e76a359e540ca786ee937da7f35faa8e5f8 ]
"intel_iommu=off" command line is used to disable iommu but iommu is force enabled in a tboot system for security reason.
However for better performance on high speed network device, a new option "intel_iommu=tboot_noforce" is introduced to disable the force on.
By default kernel should panic if iommu init fail in tboot for security reason, but it's unnecessory if we use "intel_iommu=tboot_noforce,off".
Fix the code setting force_on and move intel_iommu_tboot_noforce from tboot code to intel iommu code.
Fixes: 7304e8f28bb2 ("iommu/vt-d: Correctly disable Intel IOMMU force on") Signed-off-by: Zhenzhong Duan zhenzhong.duan@gmail.com Tested-by: Lukasz Hawrylko lukasz.hawrylko@linux.intel.com Acked-by: Lu Baolu baolu.lu@linux.intel.com Link: https://lore.kernel.org/r/20201110071908.3133-1-zhenzhong.duan@gmail.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/kernel/tboot.c | 3 --- drivers/iommu/intel-iommu.c | 5 +++-- include/linux/intel-iommu.h | 1 - 3 files changed, 3 insertions(+), 6 deletions(-)
diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c index a49fe1dcb47e8..bded81591ad95 100644 --- a/arch/x86/kernel/tboot.c +++ b/arch/x86/kernel/tboot.c @@ -512,9 +512,6 @@ int tboot_force_iommu(void) if (!tboot_enabled()) return 0;
- if (intel_iommu_tboot_noforce) - return 1; - if (no_iommu || swiotlb || dmar_disabled) pr_warning("Forcing Intel-IOMMU to enabled\n");
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 1147626f0d253..984c7a6ea4fe8 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -179,7 +179,7 @@ static int rwbf_quirk; * (used when kernel is launched w/ TXT) */ static int force_on = 0; -int intel_iommu_tboot_noforce; +static int intel_iommu_tboot_noforce; static int no_platform_optin;
#define ROOT_ENTRY_NR (VTD_PAGE_SIZE/sizeof(struct root_entry)) @@ -4927,7 +4927,8 @@ int __init intel_iommu_init(void) * Intel IOMMU is required for a TXT/tboot launch or platform * opt in, so enforce that. */ - force_on = tboot_force_iommu() || platform_optin_force_iommu(); + force_on = (!intel_iommu_tboot_noforce && tboot_force_iommu()) || + platform_optin_force_iommu();
if (iommu_init_mempool()) { if (force_on) diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h index e54d51308f6f5..6b559d25a84ee 100644 --- a/include/linux/intel-iommu.h +++ b/include/linux/intel-iommu.h @@ -706,7 +706,6 @@ extern int iommu_calculate_agaw(struct intel_iommu *iommu); extern int iommu_calculate_max_sagaw(struct intel_iommu *iommu); extern int dmar_disabled; extern int intel_iommu_enabled; -extern int intel_iommu_tboot_noforce; extern int intel_iommu_gfx_mapped; #else static inline int iommu_calculate_agaw(struct intel_iommu *iommu)