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

From: Auger Eric
Date: Tue Mar 31 2020 - 12:19:40 EST


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 <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]
>