From: Jacob Pan <jacob.jun.pan@linux.intel.com>
Date: Thu, 2 Jan 2020 00:18:09 +0000 (+0800)
Subject: iommu/vt-d: Avoid sending invalid page response
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=5f75585e19cc7018bf2016aa771632081ee2f313;p=linux.git

iommu/vt-d: Avoid sending invalid page response

Page responses should only be sent when last page in group (LPIG) or
private data is present in the page request. This patch avoids sending
invalid descriptors.

Fixes: 5d308fc1ecf53 ("iommu/vt-d: Add 256-bit invalidation descriptor support")
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---

diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index f0410e29fbc13..7c6a6e8b1c96e 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -679,11 +679,10 @@ static irqreturn_t prq_event_thread(int irq, void *d)
 			if (req->priv_data_present)
 				memcpy(&resp.qw2, req->priv_data,
 				       sizeof(req->priv_data));
+			resp.qw2 = 0;
+			resp.qw3 = 0;
+			qi_submit_sync(&resp, iommu);
 		}
-		resp.qw2 = 0;
-		resp.qw3 = 0;
-		qi_submit_sync(&resp, iommu);
-
 		head = (head + sizeof(*req)) & PRQ_RING_MASK;
 	}