From 9d6ab26a75f47332da9949a0112727e10f2d6e51 Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Tue, 10 May 2022 10:34:04 +0800 Subject: [PATCH] iommu/vt-d: Block force-snoop domain attaching if no SC support In the attach_dev callback of the default domain ops, if the domain has been set force_snooping, but the iommu hardware of the device does not support SC(Snoop Control) capability, the callback should block it and return a corresponding error code. Signed-off-by: Lu Baolu Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Link: https://lore.kernel.org/r/20220508123525.1973626-1-baolu.lu@linux.intel.com Link: https://lore.kernel.org/r/20220510023407.2759143-6-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel --- drivers/iommu/intel/iommu.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index f200af2233d0b..23985cb5c8ee3 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4333,6 +4333,9 @@ static int prepare_domain_attach_device(struct iommu_domain *domain, if (!iommu) return -ENODEV; + if (dmar_domain->force_snooping && !ecap_sc_support(iommu->ecap)) + return -EOPNOTSUPP; + /* check if this iommu agaw is sufficient for max mapped address */ addr_width = agaw_to_width(iommu->agaw); if (addr_width > cap_mgaw(iommu->cap))