From: Tina Zhang tina.zhang@intel.com
commit 7fc961cf7ffcb130c4e93ee9a5628134f9de700a upstream.
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 tina.zhang@intel.com Link: https://lore.kernel.org/r/20221115070346.1112273-1-tina.zhang@intel.com Signed-off-by: Lu Baolu baolu.lu@linux.intel.com Link: https://lore.kernel.org/r/20221116051544.26540-3-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/intel/pasid.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -652,7 +652,7 @@ int intel_pasid_setup_second_level(struc * 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); @@ -695,7 +695,8 @@ int intel_pasid_setup_pass_through(struc * 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);