Re: [PATCH 09/10] iommu/vt-d: Avoid sending invalid page response

From: Lu Baolu
Date: Sun Nov 17 2019 - 20:57:52 EST


Hi,

On 11/16/19 7:09 AM, Jacob Pan wrote:
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@xxxxxxxxxxxxxxx>

Acked-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>

Best regards,
baolu

---
drivers/iommu/intel-svm.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index a223ae93b269..189865501411 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -688,11 +688,10 @@ 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;
}