Re: [PATCH] iommufd: Require drivers to supply the cache_invalidate_user ops

[Yi Liu <yi.l.liu@intel.com>]

On 2024/6/29 05:27, Nicolin Chen wrote:
> On Fri, Jun 28, 2024 at 01:11:11PM -0300, Jason Gunthorpe wrote:
> 
>> All existing drivers implement this op for nesting, this is mostly a
>> bisection aid.
>>
>> Fixes: 8c6eabae3807 ("iommufd: Add IOMMU_HWPT_INVALIDATE")
>> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Reviewed-by: Yi Liu <yi.l.liu@intel.com>

>> ---
>>   drivers/iommu/iommufd/hw_pagetable.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
>> index 33d142f8057d70..a9f1fe44c4c0bd 100644
>> --- a/drivers/iommu/iommufd/hw_pagetable.c
>> +++ b/drivers/iommu/iommufd/hw_pagetable.c
>> @@ -236,7 +236,8 @@ iommufd_hwpt_nested_alloc(struct iommufd_ctx *ictx,
>>   	}
>>   	hwpt->domain->owner = ops;
>>   
>> -	if (WARN_ON_ONCE(hwpt->domain->type != IOMMU_DOMAIN_NESTED)) {
>> +	if (WARN_ON_ONCE(hwpt->domain->type != IOMMU_DOMAIN_NESTED ||
>> +			 !hwpt->domain->ops->cache_invalidate_user)) {
>>   		rc = -EINVAL;
>>   		goto out_abort;
> 
> Oh, we had that initially, yet lost it when splitting the series.
> 
> Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>

yes, it was dropped in v7 per a bisect concern as well. :(

v7: 
https://lore.kernel.org/linux-iommu/20231221153948.119007-1-yi.l.liu@intel.com/
  - Remove domain->ops->cache_invalidate_user check in hwpt alloc path due
    to failure in bisect (Baolu)

-- 
Regards,
Yi Liu