Re: [PATCH] iommu/vt-d: Fix PASID cache flush

From: Jacob Pan
Date: Tue Mar 31 2020 - 12:03:30 EST


Actually, this is not a bug. The current code has:
#define QI_PC_PASID_SEL (QI_PC_TYPE | QI_PC_GRAN(1))

Which already has the type and shift.

In my vSVA series, I redefined granu such that I can use them in the 2D
table lookup.

-#define QI_PC_ALL_PASIDS (QI_PC_TYPE | QI_PC_GRAN(0))
-#define QI_PC_PASID_SEL (QI_PC_TYPE | QI_PC_GRAN(1))
+/* PASID cache invalidation granu */
+#define QI_PC_ALL_PASIDS 0
+#define QI_PC_PASID_SEL 1

Please ignore this, sorry about the confusion.

On Tue, 31 Mar 2020 11:28:17 +0200
Auger Eric <eric.auger@xxxxxxxxxx> wrote:

> Hi Jacob,
>
> On 3/31/20 1:25 AM, Jacob Pan wrote:
> > PASID cache type and shift of granularity bits are missing in
> > the current code.
> >
> > Fixes: 6f7db75e1c46 ("iommu/vt-d: Add second level page table
> > interface")
> >
> > Cc: Eric Auger <eric.auger@xxxxxxxxxx>
> > Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> Reviewed-by: Eric Auger <eric.auger@xxxxxxxxxx>
>
> Thanks
>
> Eric
>
> > ---
> > drivers/iommu/intel-pasid.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/iommu/intel-pasid.c
> > b/drivers/iommu/intel-pasid.c index 22b30f10b396..57d05b0fbafc
> > 100644 --- a/drivers/iommu/intel-pasid.c
> > +++ b/drivers/iommu/intel-pasid.c
> > @@ -365,7 +365,8 @@ pasid_cache_invalidation_with_pasid(struct
> > intel_iommu *iommu, {
> > struct qi_desc desc;
> >
> > - desc.qw0 = QI_PC_DID(did) | QI_PC_PASID_SEL |
> > QI_PC_PASID(pasid);
> > + desc.qw0 = QI_PC_DID(did) | QI_PC_GRAN(QI_PC_PASID_SEL) |
> > + QI_PC_PASID(pasid) | QI_PC_TYPE;
> > desc.qw1 = 0;
> > desc.qw2 = 0;
> > desc.qw3 = 0;
> >
>

[Jacob Pan]