Re: [PATCH v5 09/11] iommu/vt-d: Add iotlb flush for nested domain

From: Yi Liu
Date: Fri Oct 13 2023 - 08:55:05 EST


On 2023/9/27 14:53, Tian, Kevin wrote:
From: Liu, Yi L <yi.l.liu@xxxxxxxxx>
Sent: Thursday, September 21, 2023 3:54 PM
+
+ /* REVISIT:
+ * VT-d has defined ITE, ICE, IQE for invalidation failure per hardware,
+ * but no error code yet, so just set the error code to be 0.
+ */
+ *cerror_idx = 0;
+

Is it "hardware doesn't provide error code now though it's defined in
spec" or "intel-iommu driver doesn't retrieve the error code though
it's provided by the hardware"?

I didn't see vtd spec defines error code for cache invalidation. :(


Is there guarantee that '0' isn't used for an existing error code or
won't be used for any new error code later?

may need to check it.

--
Regards,
Yi Liu