| From ddf2d884ece7d6b32e6d8782da6c0b144f3f98a5 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Sat, 20 Mar 2021 10:41:56 +0800 |
| Subject: iommu/vt-d: Don't set then clear private data in prq_event_thread() |
| |
| From: Lu Baolu <baolu.lu@linux.intel.com> |
| |
| [ Upstream commit 1d421058c815d54113d9afdf6db3f995c788cf0d ] |
| |
| The VT-d specification (section 7.6) requires that the value in the |
| Private Data field of a Page Group Response Descriptor must match |
| the value in the Private Data field of the respective Page Request |
| Descriptor. |
| |
| The private data field of a page group response descriptor is set then |
| immediately cleared in prq_event_thread(). This breaks the rule defined |
| by the VT-d specification. Fix it by moving clearing code up. |
| |
| Fixes: 5b438f4ba315d ("iommu/vt-d: Support page request in scalable mode") |
| Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> |
| Reviewed-by: Liu Yi L <yi.l.liu@intel.com> |
| Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> |
| Link: https://lore.kernel.org/r/20210320024156.640798-1-baolu.lu@linux.intel.com |
| Signed-off-by: Joerg Roedel <jroedel@suse.de> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/iommu/intel/svm.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c |
| index 8670cddadc91..ac86509a0a73 100644 |
| --- a/drivers/iommu/intel/svm.c |
| +++ b/drivers/iommu/intel/svm.c |
| @@ -1071,12 +1071,12 @@ no_pasid: |
| QI_PGRP_RESP_TYPE; |
| resp.qw1 = QI_PGRP_IDX(req->prg_index) | |
| QI_PGRP_LPIG(req->lpig); |
| + resp.qw2 = 0; |
| + resp.qw3 = 0; |
| |
| if (req->priv_data_present) |
| memcpy(&resp.qw2, req->priv_data, |
| sizeof(req->priv_data)); |
| - resp.qw2 = 0; |
| - resp.qw3 = 0; |
| qi_submit_sync(iommu, &resp, 1, 0); |
| } |
| prq_advance: |
| -- |
| 2.30.2 |
| |
