2020-03-30 23:20:37

by Jacob Pan

[permalink] [raw]
Subject: [PATCH] iommu/vt-d: Fix PASID cache flush

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 <[email protected]>
Signed-off-by: Jacob Pan <[email protected]>
---
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;
--
2.7.4


2020-03-31 09:29:02

by Eric Auger

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

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 <[email protected]>
> Signed-off-by: Jacob Pan <[email protected]>
Reviewed-by: Eric Auger <[email protected]>

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;
>

2020-03-31 16:04:45

by Jacob Pan

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

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 <[email protected]> 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 <[email protected]>
> > Signed-off-by: Jacob Pan <[email protected]>
> Reviewed-by: Eric Auger <[email protected]>
>
> 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]

2020-03-31 16:22:03

by Eric Auger

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

Hi Jacob,

On 3/31/20 6:08 PM, Jacob Pan wrote:
> 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.
OK I missed that as well, sorry. So that's not a fix but the code will
become more readable/consistent in your vSVA series.

Thanks

Eric
>
> On Tue, 31 Mar 2020 11:28:17 +0200
> Auger Eric <[email protected]> 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 <[email protected]>
>>> Signed-off-by: Jacob Pan <[email protected]>
>> Reviewed-by: Eric Auger <[email protected]>
>>
>> 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]
>