From 7fc961cf7ffcb130c4e93ee9a5628134f9de700a Mon Sep 17 00:00:00 2001 From: Tina Zhang Date: Wed, 16 Nov 2022 13:15:44 +0800 Subject: [PATCH] iommu/vt-d: Set SRE bit only when hardware has SRS cap SRS cap is the hardware cap telling if the hardware IOMMU can support requests seeking supervisor privilege or not. SRE bit in scalable-mode PASID table entry is treated as Reserved(0) for implementation not supporting SRS cap. Checking SRS cap before setting SRE bit can avoid the non-recoverable fault of "Non-zero reserved field set in PASID Table Entry" caused by setting SRE bit while there is no SRS cap support. The fault messages look like below: DMAR: DRHD: handling fault status reg 2 DMAR: [DMA Read NO_PASID] Request device [00:0d.0] fault addr 0x1154e1000 [fault reason 0x5a] SM: Non-zero reserved field set in PASID Table Entry Fixes: 6f7db75e1c46 ("iommu/vt-d: Add second level page table interface") Cc: stable@vger.kernel.org Signed-off-by: Tina Zhang Link: https://lore.kernel.org/r/20221115070346.1112273-1-tina.zhang@intel.com Signed-off-by: Lu Baolu Link: https://lore.kernel.org/r/20221116051544.26540-3-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel --- drivers/iommu/intel/pasid.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c index c30ddac..e13d7e5 100644 --- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -642,7 +642,7 @@ int intel_pasid_setup_second_level(struct intel_iommu *iommu, * Since it is a second level only translation setup, we should * set SRE bit as well (addresses are expected to be GPAs). */ - if (pasid != PASID_RID2PASID) + if (pasid != PASID_RID2PASID && ecap_srs(iommu->ecap)) pasid_set_sre(pte); pasid_set_present(pte); spin_unlock(&iommu->lock); @@ -685,7 +685,8 @@ int intel_pasid_setup_pass_through(struct intel_iommu *iommu, * We should set SRE bit as well since the addresses are expected * to be GPAs. */ - pasid_set_sre(pte); + if (ecap_srs(iommu->ecap)) + pasid_set_sre(pte); pasid_set_present(pte); spin_unlock(&iommu->lock); -- 2.7.4