On 02/07/2024 17:29, CLEMENT MATHIEU--DRIF wrote:
On 02/07/2024 15:33, Yi Liu wrote:
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On 2024/7/2 13:52, CLEMENT MATHIEU--DRIF wrote:
From: Clément Mathieu--Drif <clement.mathieu--d...@eviden.com>
Signed-off-by: Clément Mathieu--Drif <clement.mathieu--d...@eviden.com>
Reviewed-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
---
hw/i386/intel_iommu.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 98996ededc..71cebe2fd3 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -3500,6 +3500,11 @@ static bool
vtd_process_wait_desc(IntelIOMMUState *s, VTDInvDesc *inv_desc)
} else if (inv_desc->lo & VTD_INV_DESC_WAIT_IF) {
/* Interrupt flag */
vtd_generate_completion_event(s);
+ } else if (inv_desc->lo & VTD_INV_DESC_WAIT_FN) {
+ /*
+ * SW = 0, IF = 0, FN = 1
+ * Nothing to do as we process the events sequentially
+ */
This code looks a bit weird. SW field does not co-exist with IF. But
either
SW or IF can co-exist with FN flag. Is it? Have you already seen a wait
descriptor that only has FN flag set but no SW nor IF flag?
Yes, my test suite triggers that condition
I think it comes from the kernel function intel_drain_pasid_prq
(https://elixir.bootlin.com/linux/latest/source/drivers/iommu/intel/svm.c#L467)
} else {
error_report_once("%s: invalid wait desc: hi=%"PRIx64",
lo=%"PRIx64
" (unknown type)", __func__, inv_desc->hi,
--
Regards,
Yi Liu
