Commit 1d421058 authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: Don't set then clear private data in prq_event_thread() 



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: 5b438f4b ("iommu/vt-d: Support page request in scalable mode")
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: default avatarLiu Yi L <yi.l.liu@intel.com>
Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20210320024156.640798-1-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 803766cb

drivers/iommu/intel/svm.c

+2 −2
Original line number Diff line number Diff line
@@ -1034,12 +1034,12 @@ static irqreturn_t prq_event_thread(int irq, void *d) 
				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: